One of the requirement set for OPIE to be supported for Angstrom was compliance with standard GNU/Linux installation location ($prefix and friends). There was bug in OE long enough for this, with few developers considering how to proceed with this.
I finally found time to test some ideas from it, and initial conversion from /opt/QtPalmtop to /usr went pretty smooth requiring besides rebuild few fixes to packages where the former path was harcoded in the literal form. Resulting opie-image booted in QEMU quite well, so I went with committing it, bumping snaphost date for OPIE 1.2.3-pre to 20070702 at the same time.
Hope other developers will help with testing it, and then the conversion needs to be fixed by moving data and plugin to appropriate locations (now they live at places like /usr/pics). This would take a bit more effort exactly because of this dichotomy - data vs plugins, with first should be living under /usr/share, and the latter (ideally) under /usr/lib. I wonder, if a solution like making QTDIR, etc. environment variables to accept list of paths is good enough (well, it is generic from system design point of view, but adds extra runtime overhead).