Well, after trying a couple ways to "fix" PUSH on my iPhone, only one thing ultimately worked solidly.

First I tried the Dev Team's solution... it didn't work... but the problem was my fault. I was using CyberDuck to readjust the permissions for the nimble and inject files and as it turns out, they weren't sticking, and I didn't realize it though I'm normally careful about that...

Second I tried the Cydia hack... it didn't work...

Third I tried the Cydia hack again some days later out of pure stuborness and miraculously enough, PUSH worked though I got notifications from potentially any number of other people sharing the same PUSH Certificate that came with the hack...

Finally, fourth time was the charm. I got fed up with the PUSH notifications I was getting so I decided to try it again on my own. Keep in mind I have an iPod Touch 1st Gen as my guinea pig. On that device, all notifications have worked perfectly, so I figured "set it up to the max with the notifications you want working and for the programs you want working on the iPhone and let's see..."

This had the best opportunity of working primarily because I used my iPod Touch's internet on a limited basis. I do use it and such, but my primary media device is definitely the iPhone. In addition to this, I figured it was best if I had my notifications split between two devices of my choosing rather than over dozens/hundreds/thousands/millions of people using hacktivated iPhones...

Then I proceeded to check out forums at iPod Touch Fans to see what experiences there had been. They were, ironically, fairly informative. I used the feedback from there on several discussions to do the following:

Push Solution Test Steps (Modified from original and short version by 007. user on iPod Touch Fans)
------------------------

A. Get Legit Keychain Data:
*You Must Perform These Steps On A Properly Activated Device (iphone or ipod touch) with at least one working push app*

1. Unzip the downloaded zip file of the PUSH Fix made by the Dev Team to the activated device with working PUSH Notifications (in my case I had set up IM+, AP Mobile & Nimbuzz) and copy the binary 'nimble' using SSH into /private/var/Keychains and set permission to 0775 - note that I did not go with 0755, and also that all permissions were handled via Terminal on the iPhone as user "root".

Commands in Terminal (MobileTerminal, available in Cydia):
1.- Type 'su' and enter the password 'alpine'
2.- Type 'cd /private/var/Keychains'
3.- Type 'chmod 0775 nimble'

2. Make sure the file "keychain-2.db" is in /private/var/Keychains and run nimble. You will see 4 files have been created as a result of running nimble:
- youtube-cert.bin
- youtube-key.bin
- push-cert.bin
- push-key.bin

Commands:
1.- Type './nimble'

3. Copy these 4 files into the corresponding folder on your hacktivated device (/private/var/Keychains) BEFORE proceeding to point "B".


B. Testing Push:
*You Must Perform These Steps On Your Hacktivated Device*

1. Copy the binaries named inject and nimble from the original zip file you downloaded before, and SSH into /private/var/Keychains, then set permissions to 0775:
- inject
- nimble

Commands:
1.- Type 'su' and enter the password 'alpine'
2.- Type 'cd /private/var/Keychains'
3.- Type 'chmod 0775 nimble'
4.- Type 'chmod 0775 inject'

2. Store the device's current "keychain-2.db" elsewhere as a backup copy in case you need to replace the one you're creating now - this step may spare you the woes of having to restore your iPhone completely if this doesn't work - and run inject. Do this quickly as the keychain-2.db seems to regenerate on its own. A new keychain-2.db will be created.

Commands:
1.- ./inject

3. Uninstall the PUSH apps (i.e. beejive, IM+, AIM, or similar) you intend to test on your hacktivated device and reboot.

4. Test YouTube to see if it's working (it might stall out the first time so try at least twice to see if it'll connect to YouTube), and if it's working, reinstall your PUSH Apps. If it's not working, you did something wrong. Either start again and make sure you're following the instructions fully, or replace the keychain-2.db on your iPhone with your saved back-up.

5. If your iPod Touch is on and connected to WiFi, disconnect it, and proceed to testing PUSH apps on your hacktivated device over Edge/WiFi/3G.

WARNINGS: If it didn't work, either PUSH notifications aren't working on your iPod Touch (did you check?) or they are not set-up as active, or you did something wrong. Start over, test the activated device you are trying to get the certificate files from, and try again.

Do yourselves a favor, do not upload your certificates to the web unless you want to be bombarded by other people's push notifications.

Finally, expect your e-mail and login settings/info to be reset as a result of fiddling around with these certificates. In my case all I had to do was go into Settings for Mail and type in all passwords again and this fixed the problem there. All other apps with logins varied: some had to be reinstalled from scratch, others only required having the login information placed in again. Make sure you have back-ups of any important files in any apps that you may potentially end up having to uninstall and reinstall...

RECOMMENDATION: Use an officially activated iPhone or iPod Touch that you are either no longer using much, if at all. The reason for this is that any time your PUSH certificate updates to whatever IP is set for your hacktivated device, the PUSH notifications will get sent to that address. So if you suddenly turn on your iPod Touch (such as in my case) either my PUSH notifications will be split between my iPhone and iPod, or the latest connected device will receive the majority if not all of the PUSH notifications.

And finally, I don't guarantee this will work. I am sure many of you will be dissatisfied by how it works... but... on the other hand some of you may not mind and finally be quite content with the results. I have been, and I have not missed a single PUSH notification since. It does suck that I have to basically limit my iPod Touch usage, but oh well, small price to pay for my iPhone to be fully functional while I get my hands on an officially activated iPhone 3Gs... That said, it seems that if you're sharing these certificates between two devices, that you can avoid the loss of messages between them so long as both devices are using different apps in the end as tried by "prof_hastig".

I can confirm that. I use the certificates from my son's iPod and since we aren't using the same PushApps we both have 100% fun with them.

The step mentions copying the 4 files into the corresponding folders. Can you identify the folder locations? I have looked and looked, but WinScp doesn't seem to have a search feature..

That would be /private/var/Keychains - same folder where you used the nimble binary on your activated device, only your are copying the four generated files to the device you are trying to activate PUSH on

Thanks for the info! Very good to know!!

Understand it now. Still need a good activated device to get the cert file to put on my hacitvated phone. Will have to wait until a new fix is in place. Thanks anyway. Nice detail to your steps.

Thanks for the solution, 100% working!

how about this:

1. make a custom firmware without hactivate the phone
2. restore the phone
3. activate with the legit SIM
4. get the files via SSH into the device
5. jailbreak with hactivated firmware (need this step? can i just insert my usual sim? )
6. copy the file into where it needs to be for Push to work.

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My iPhone:
8GB Pwned at 3.0 with working MMS

(youtube always worked)
Tried manual install of the fix.
Got 5 PUSHed IMs from AIM.
No more, for a day. tried fring, and notifyme... no luck.
So I tried the cydia based Push fix. No luck
uninstalled, reinstalled. no luck
uninstalled, reinstalled, still, no luck.
unistalled. IT STARTED WORKING!?
Was really inconstant. Worked sometimes, couldnt link it to a problem with anyone particular. airplane mode fixed it once, but not reliably.
Then I noticed that Youtube didnt, work.
So I reinstalled the push fix... bricked. wouldnt get through bootup.

Restored.

Tested youtube, didnt work.
So I installed Push Fix.
youtube works.
Push Apps say I need to connect to itunes. No push now.

Uninstalled.

Worth trying again?

Worth trying again?

Not unless you will be happy with inconsistent pushed messages (sometimes it works and sometimes it doesn't) and happy with receiving random other push notifications from strangers.

I've installed "backgrounder" for now which was updated for 3.0 and monitoring the battery life. I've subscribed to this thread and I'll certainly try again if/when dev team or someone clever manages to get a better work-around than the current "certificate sharing".