FW: MemBufInputSource throwing exception

I'm using xerces-c_2_7 in a multi-threaded environment on Win32 XP.

Every now and then I get an exception thrown on this line( try/catch removed
for brevity):

 

MemBufInputSource* source = new MemBufInputSource((const XMLByte*)raw,
(unsigned int)strlen( raw ), "IC15", false);

 

I can't see anything in the header file or API doc about what might cause
this to throw an exception. My raw data is UTF8, and the lengths are
typically 50-100K bytes.

 

I can't tell what type of Exception it is throwing. It's not a DOM or SAX
Exception but a general catch(.)

 

Should the "IC15" identifier be unique across threads? The docs suggest that
this id isn't relevant other than for reporting.

 

Thanks,

Graeme