.c/.cpp - mapping to compiler

IspcCGenHFile.cpp fast
cc: Warning: illegal option -nstances=static
cc: No input file specified, no output generated
Error while executing "cc -DREL30 -DSVR4 -DI386 -DSAG -I/home/doehrm/sa\
pdb/TOOLSRC/sys/wrk/incl/SAPDB/STLport/stlport -I/home/doehrm/sapdb/TOOL\
SRC/sys/wrk/incl/SAPDB -I/home/doehrm/sapdb/TOOLSRC/usr/incl -I/home/doe\
hrm/sapdb/TOOLSRC/sys/wrk/incl -I/home/doehrm/sapdb/TOOLSRC/sys/wrk/incl\
/SAPDB -Xa -D_SVID -DSOLARIS7 -KPIC -instances=static -DFAST=FAST -DSAPD\
B_FAST -xO4 -I/home/doehrm/sapdb/TOOLSRC/incl -c IspcCGenHFile.cpp"

Since this is a .cpp file it should be compiled with CC but it's using cc. 

toolvarsDump.pl is showing, that the compilers are detected correctly:

[...]
CC
cc
[...]
CXX
CC
[...]

Can anyone please give me a hint where to look? 

-- 
Markus Doehr            	     SIEGENIA-AUBI KG
CCC - SAP R/3 Basis, SAPDB-DBA     Industriestr. 1 - 3 
fon: +49 6503 917 152              57234 Wilnsdorf-Niederdielfen
fax: +49 6503 917 190              http://www.siegenia-aubi.com