Since you alloc'd it, you'll need to release it. Just release it after calling parse:
BOOL rval = [provisioningParser parse];
[provisioningParser release];
return rval;
Also, from the looks of your code, it looks like you might be saving this in a member variable. Is there a reason for doing that? If not, make it a local variable. If so, you'll probably want to release it in the dealloc() method of your class instead of after calling parse().