src/timezone/pgtz __imp__my_exec_path

beta4 - cygwin:
postgres.exe fails to build, because __imp__my_exec_path from
src/timezone/pgtz.o cannot be resolved. previously it was not imported.

dlltool --dllname postgres.exe --output-exp postgres.exp --def postgres.def
gcc -O2 -Wall -Wmissing-prototypes -Wpointer-arith -Wendif-labels
-fno-strict-aliasing -L../../src/port -L/usr/local/lib  -o postgres.exe
-Wl,--base-file,postgres.base postgres.exp access/SUBSYS.o
bootstrap/SUBSYS.o catalog/SUBSYS.o parser/SUBSYS.o commands/SUBSYS.o
executor/SUBSYS.o lib/SUBSYS.o libpq/SUBSYS.o main/SUBSYS.o
nodes/SUBSYS.o optimizer/SUBSYS.o port/SUBSYS.o postmaster/SUBSYS.o
regex/SUBSYS.o rewrite/SUBSYS.o storage/SUBSYS.o tcop/SUBSYS.o
utils/SUBSYS.o ../../src/timezone/SUBSYS.o  -lpgport_srv -lintl -lssl
-lcrypto -lz -lreadline -lcrypt -lresolv
../../src/timezone/SUBSYS.o(.text+0x2192):pgtz.c: undefined reference to
`__imp__my_exec_path'

nm postgresql-8.0.0beta4/src/timezone/pgtz.o |grep my_exec
          U __imp__my_exec_path
but:
nm postgresql-8.0.0beta3/src/timezone/pgtz.o |grep my_exec
          U _my_exec_path

The makefile didn't change. The src, cmdline and def file is also the
same. It might related to some change in the header files with the
pgport_srv seperation.
Can somebody give me a hint?
--
Reini Urban
http://xarch.tu-graz.ac.at/home/rurban/