Both melodies are based on a fairly standard pattern and a fairly standard chord progression. To me they do sound similar but not exactly the same, it may happen that they were written independently
For the record, the PPK track is based on this (written in late 70's)
The PPK track was released in 2002 (EDIT: actually 1999). I remember it well, basically it was one of the first trance tracks I've ever heard.
And I have to say that listening to it now gives me goosebumps. It sounds dated but club trance as a whole had certain charm in early 00's.