diff --git a/o/OpenMPI/OpenMPI-4.0.0-GCC-6.3.0-2.27.eb b/o/OpenMPI/OpenMPI-4.0.0-GCC-6.3.0-2.27.eb
index ca6fe551..04551d84 100644
--- a/o/OpenMPI/OpenMPI-4.0.0-GCC-6.3.0-2.27.eb
+++ b/o/OpenMPI/OpenMPI-4.0.0-GCC-6.3.0-2.27.eb
@@ -12,6 +12,7 @@ toolchain = {'name': 'GCC', 'version': '6.3.0-2.27'}
 
 source_urls = ['https://github.com/open-mpi/ompi/archive/']
 sources = ['v4.0.0.tar.gz']
+checksums = ['79cbd68a18b9992f33ae18c1478031945ea941c3560f9203d5890bfe76b38d91']
 
 dependencies = [
     ('hwloc', '2.0.3'),
@@ -19,8 +20,8 @@ dependencies = [
 ]
 
 # for PBS Pro 13
-preconfigopts = 'export LIBS="-ldl" && '
-preconfigopts += './autogen.pl && '
+#preconfigopts = 'export LIBS="-ldl" && '
+preconfigopts = './autogen.pl && '
 
 configopts = '--enable-shared --enable-mpi-thread-multiple --with-verbs '
 # suppress failure modes in relation to mpirun path