Do you mean HP-UX? Have you read the man pages and other documentation?

I think recent versions of HP-UX may use the same ELF object format, including .so files, as Solaris and Linux do now too.

But in any case, since you have to use the native compiler tools anyway (do you use some HP compiler? or GNU gcc?), they should build the right kind of object files for that OS, so read their doc and make sure your Makefiles use the appropriate settings etc.