diff --git a/gdbm.spec b/gdbm.spec
index 2d5b6e1..a1bc5a9 100644
--- a/gdbm.spec
+++ b/gdbm.spec
@@ -1,7 +1,7 @@
 Summary: A GNU set of database routines which use extensible hashing
 Name: gdbm
 Version: 1.8.3
-Release: 5%{?dist}
+Release: 6%{?dist}
 Source: http://ftp.gnu.org/gnu/gdbm/gdbm-%{version}.tar.gz
 # Prevent gdbm from storing uninitialized memory content
 # to database files.
@@ -61,6 +61,14 @@ autoconf
 
 %build
 %configure --disable-static
+
+# flock does not work on nfs
+# fcntl should be used instead of it
+# see `man 2 flock`
+# rhbz#477300
+echo "/* We use fcntl locking (POSIX) instead of flock (BSD) */" >> autoconf.h
+echo "#undef HAVE_FLOCK" >> autoconf.h
+
 make
 
 %install
@@ -103,6 +111,9 @@ fi
 rm -rf ${RPM_BUILD_ROOT}
 
 %changelog
+* Mon Apr 12 2010 Karel Klic <kklic@redhat.com> - 1.8.3-6
+- Use fcntl instead of flock for locking to make nfs safe (#477300)
+
 * Thu Mar 11 2010 Karel Klic <kklic@redhat.com> - 1.8.3-5
 - Removed fake Provides: libgdbm.so.2 and corresponding symlinks
 - Moved autoconf, libtoolize from %%build to %%prep section