do I need to initialize XPCOM to use string classes?

Dear list:

I am using the string classes nsString, nsAutoString, 
nsDependentCString, nsSharableString in a non-mozilla application.  Do I 
need to initialize XPCOM or NSPR before i use these classes?  Also, I am 
linking these classes in using a static build... I am presuming that I 
need to define _IMPL_NS_COM so that the string headers are not declared 
dllexport.  Are there any other problems that I might need worry about?

Benjamin Smedberg