[Scratchbox-users] Making sb-provided m4 prefer files from /usr/share/aclocal

[Matt Hoosier]

A package that I'm patching [X.org server from the 7.1 release]
requires a newer version of pkg-config macros than those shipped with
0.15 (the version provided by SB). After building and installing
pkg-config 0.19, the m4 engine provided by Scratchbox still finds the
pkg-config macros from /scratchbox/tools/share/aclocal/pkg.m4, rather
than my newer file installed at /usr/share/aclocal/pkg.m4.

If I manually move /scratchbox/tools/share/aclocal/pkg.m4 out of the
way, autoconf finds the updated version with no problem.

Is there an environment variable which I can tweak in order to put
/usr/share/aclocal in the search path ahead of
/scratchbox/tools/share/aclocal? During Debian package builds, it's
not really feasible to manually gain root powers and move the
SB-provided file out of the way each time. I tried manipulating
M4PATH, but this seems to have no effect.

Thanks,

Matt