[dev] wmii; make with /bin/bash not with /bin/sh

Hello dear subscribers,

when compiling the wmii+ixp-3.9b1 on a solaris box, make calls /bin/sh
to evaluate several scripts. Since /bin/sh is really old around here,
make dies instantly because /bin/sh can't interpret the scripts ("/bin
sh: bad substitution").
Since relinking /bin/sh to /bin/bash is neiter a decent nor any option
here, how do I get make to use /bin/bash and not /bin/sh?

Measures tried:
  - resetting PATH, since make calls /bin/sh and not sh it is never
looked up there
  - setting BINSH or SHELL to /bin/bash won't work either.
  - Asking for help at #suckless did not come up with immediate solution.

The only thing that came up on #suckless was LD_PRELOAD to overwrite the
system calls... but that might take some time to do and is not a clean
option either. But it looks interesting enough to try out some time.

Any ideas?

-- 
regards,
David