I just followed the instruction on docwiki.gumstix.org/Buildroot, selecting only the additional package uisp. When I try to make I get:

checking for gawk... gawk
checking whether make sets $(MAKE)... yes
checking for arm-linux-strip... arm-linux-strip
checking for arm-linux-g++... /home/claudio/gumstix-buildroot
checking for C++ compiler default output file name... configure: error: C++ compiler cannot create executables
See `config.log' for more details.
make: *** [/home/claudio/gumstix-buildroot/build_arm_nofpu/uisp-20050207/.configured] Error 77

I find out that someone had the same problem on the mailing list, but no one answered.

However, I tried to cross compilate by myself (as suggested in http://docwiki.gumstix.org/Gumstix_programming):

./configure --host=arm-linux --prefix=/home/claudio/gumstix-buildroot/build_arm_nofpu/root
make && make install

then I reflashed the gumstix. Now I have the error:

/bin/uisp: /bin/uisp: 1: Syntax error: "(" unexpected

Any idea?