This does the trick for me on Ubuntu 12.10/amd64:
# be sure to build static versions of all included libraries
$ ./configure --enable-static
$ make
$ cd hw/vfb
$ make clean
# this provides static versions of some functions which are dynamic only in eglibc
$ sudo apt-get install libtirpc-dev
# LDFLAGS=-all-static asks libtool to do static linking
# LD_EXPORT_SYMBOLS_FLAGS= causes --export-dynamic to be omitted
# LIBS='...' fills in missing dependencies for static libraries
$ make LDFLAGS=-all-static LD_EXPORT_SYMBOLS_FLAG= LIBS='-lfreetype -lgpg-error -lfontenc -ltirpc -lz -lbz2 -lm -lrt -lpthread'
This is a bit of a hack for two reasons:
It hardcodes the library dependencies (which could change in other versions of X)
It introduces an odd dependency on libtirpc. Without it, I got unresolved symbols for xdrmem_create(3) and a few other things which are provided by libnsl when linking dynamically:
/tmp/xorg-server-1.13.0/os/rpcauth.c:79: undefined reference to `xdrmem_create'