Additional information:
To avoid the problem I now use a mutex to serialize the access. It works almost good!
But now Powerbuilder crashes only sometimes at access of variablelist property:
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Microsoft Visual C++ Runtime Library
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Runtime Error!
Program: C:\Program Files (x86)\Sybase\PowerBuilder 12.0\PB120.EXE
R6025
- pure virtual function call
Any ideas what's the reason?