Could you pos the output from (the -v switch gives more details):
./kbs.tcl -v -r -mk install kbskit8.6
Also check the output of
./kbs.tcl config
on the line
[Get exec-make] = /usr/bin/gmake
and see if the given 'make' program ca handle 'VPATH'.
'gmake' can do but some other under solaris have problems.