If I remember my "c" correctly, the second parameter required by GetErrorStr is a POINTER to a pre-allocated null-terminated string.

You may have better luck trying the following: 

$obj->GetErrorStr( Variant(VT_I4|VT_BYREF, 12345), \$errstr ); 
#Notice REFERENCE to $errstr

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In reply to Re: in/out Win32:Ole strings by NetWallah
in thread in/out Win32:Ole strings by RonJames

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