Show memory leaks in dll?

Hello,

when ending my app in the debugger, memory leaks will be shown like this:
Detected memory leaks!
Dumping objects ->
C:\PROGRAM FILES\VISUAL STUDIO\MyProjects\leaktest\leaktest.cpp(20) : {18}
normal block at 0x00780E80, 64 bytes long.
Data: < > CD CD CD CD CD CD CD CD CD CD CD CD CD CD CD CD
Object dump complete.

How can I tell Visual c++ also to show me the memory leaks in a called dll?

thx
Ralf