This is from another post I had - just for clarification..
All HP-UX versions since the early 90's have supported multipathing (aka PVLinks). Some arrays require special software(an older EVAs (3K/5K) is an example) for multipath support. This is an exception to the rule, as most arrays HP sells are A/A.
There is software for load balancing that is provided (aka Autopath, and now SecurePath) which was not avaialble until the early 00's. With the release of 11i v3, they have now built load balancing in to the mass storage stack, and improved the naming and addressing schema (no more cXtYdZ, just disk1, etc).
Just to reiterate - HP-UX has native multipathing built in - no special software required (with the EXCEPTION of the A/P VCS versions of the EVA3/5000).
Sincerely,
Curt
"In Vino Veritas"