message explanation

[Hirsch, Elliot]

Hi,
I received the following message during a ddd session:

Watchpoint 3 deleted because the program has left the block in which its
expression is valid.
0xfeas1ed9c in Vos_Mutex_Acquire () from
/tools/opnet.../sun_sparc_solaris/lib/libopvos.so

What does this mean? Did me program enter an invalid area? Am I leaking
memory? How do I avoid this?
Thanks in advance for your help,
Elliot

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