3.6 to 4.2 relative versus absolute data path issue

[Adam Simcock]

We are in the process of moving to mapserver 4.2 from 3.6.   The mapfiles we
have generally use relative paths to data.   Updating to 4.2 causes two
relative pathname issues to occur:

1) When I switch over to the 4.2 executables, raster data in AI grid format
does not display.  If I change those data paths to absolute, it displays.
This is only happening with AI grid files – a tif raster is displaying with
relative paths without a problem.  The relative paths are correct and work
fine in 3.6.

2) Vector files display fine with relative paths, but opening shapefiles in
PHP mapscript only works if I switch them over to absolute paths in the
mapfile.  The relative paths are correct and work fine in 3.6.

The problem has been isolated to the 3.6 to 4.2 switch – tested on the same
windows server.  We have a LOT of mapfiles/projects with many layers in
each, really want to avoid having to change them all to absolute
pathnames
would also make it difficult to move around projects
(mapfile/dataset combinations) on the server.

Thanks,
Adam Simcock
EarthIT