Archived:Front-End Processors (FEPs) can crash some system apps in S60 2nd Edition FP1 and FP2 (Known Issue)
Third-party FEPs will crash some system applications, such as browser.
System applications require that a FEP implements a specific interface which is not part of the public SDK.
How to reproduce
Use Series 60 Developer Platform 1.0: FEP Example v1.0.
Currently no solution exists.