Not used the treo 700p yet but:
According to the Skyscape website, the 5MCC works on OS version 3.5 and up (presumably this includes 5.4).
With epocrates, they say required Palm 5 or higher so should work.
http://www.epocrates.com/products/rx/requirements.html
Can't find anything about JH ABX I'm afraid.
If you want to be sure, you could try firing off a few emails to the support for Skyscape and Epocrates.
Chris
__________________
Dr Chris Paton BMBS BMedSci (Notts UK)
Lecturer in Health Informatics, University of Otago, New Zealand.
www.hein.otago.ac.nz
CEO, New Media Medicine Ltd, e-Learning for Healthcare.
www.newmediamedicine.com