Problems with pg_dump for PG8.4 for WinXP (MinGW build)

Hello!
I need PG 8.4 built from source code for WinXP. So I got archive postgresql-8.4.1.tar.gz, unpacked it and built postgres by MinGW, as usual:
configure --witout-zlib
make
make install

Everything seeds to be fine until we tried to test pg_dump. It failed (not always but often).
Command:
pg_dump -U postgres -v -f mydump.sql TEST_DB

The end of output:
pg_dump: reading triggers for table "test_table"
pg_dump: reading dependency data
pg_dump: saving encoding = UTF8
pg_dump: saving standard_conforming_string = off
pg_dump: saving database definition

And here we get a message 'an unhandled win32 exception occured in pg_dump.exe(1788)'
(digits in brackets varies for different runs of pg_dump)

There are no such problems for ready biniries.

Regards, Marina.