The app TubeDeluxe (a London underground map app) has been updated today to include a route planner, but the planner doesn't work on jailbroken iPhones. According to the dev's website:

"Why does journey planning not work on Jail Broken devices?
In short, I don't know. It's a low level (technical: a core library running on thread 0 in the jail broken OS, probably a memory pointer exception) problem with the jail broken operating system itself. A lot of intensive activity occurs when the journey plan is calculated, this works flawlessly on a genuine OS installations, clearly something is different in the jail broken OS. This is something for iPhone Dev Team (the group that regularly jail breaks the OS) to fix rather than for me provide a work around. I develop for Apple iPhone & iPod Touch OS, if it works on jail broken devices, that's great, if it doesn't, it is not my problem. That said, the problem is not something I have deliberately introduced."

Does anyone know if this problem affects any other apps, and if the Dev Team knows about / is planning to fix it?