Some of our users get this problem with the outlook connector on xp/outlook 2003 when sending mails: (connector and server 5.0.7)

Microsoft Visuel C++ Debug Library:

Debug Assertion Failed
Program: ...Office\Office12\OUTLOOK.EXE
File: ...franklin-507/mapi/src/sharingaddin/addin.cpp
Line: 1610

Expression: g_pAddinInstance
...

Any ideas?
The mail gets sent, though...