make install problem - lib/expat_external.h

I am attempting to build and install Expat 1.95.8 on Solaris 8 with gcc. 
"configure; make; make install" all run without errors, but the file
lib/expat_external.h does not get installed.

Here is a line of output from "make install":

conftools/install-sh -c -m 644 ./lib/expat.h ./lib/expat_external.h
/opt/DCIexpat/1.95.8/include

But only one file got installed:

bash-2.03# ls -l /opt/DCIexpat/1.95.8/include/
total 80
-rw-r--r--   1 root     other      40115 Aug 26 10:03 expat.h
bash-2.03# pwd

Here is an excerpt from conftools/install-sh:

# This script is compatible with the BSD install script, but was written
# from scratch.  It can only install one file at a time, a restriction
# shared with many OS's install programs.

It looks like make is trying to install both files with one call to
install-sh, although install-sh doesn't support it.