I've just pushed out an update to syslog-ng, which contains various HP-UX fixes backported from the Premium Edition of syslog-ng.
The GPL version of syslog-ng should now work flawlessly on HP-UX. There's one caveat though: there's a buggy system header in HP-UX and gcc 4.x fails to compile it. I copied this header to the gcc private include directory (/usr/local/lib/gcc/hppa2.0w-hp-hpux11.11/4.1.0/include on my system) and applied the following patch:
> #ifndef _APP32_64BIT_OFF_T
(HP-UX diff does not know how to produce unified diffs), the point is that there are two conflicting declarations of a function and the preprocessor conditional above fixes that. Once this patch is in place, and you have the proper build dependencies syslog-ng works fine on HP-UX.
As I've just pushed these changes to my git repository, you'll need to wait for another day to get a daily snapshot. But hey "git" is what the pros use :)