diff --git a/modules/conop/tests/test_complib.py b/modules/conop/tests/test_complib.py
index 99ef78d5a1904cdb257c07ac1fd936292917e45e..960d65e0a1dc4be9c72e8816f226ede595c6bd41 100644
--- a/modules/conop/tests/test_complib.py
+++ b/modules/conop/tests/test_complib.py
@@ -3,6 +3,7 @@ import ost
 from ost import conop
 import subprocess
 import tempfile
+import warnings
 
 
 class TestCompLib(unittest.TestCase):
@@ -43,6 +44,15 @@ class TestCompLib(unittest.TestCase):
         self.assertTrue(comp_nh4.atom_specs[0].charge == 1)
         self.assertTrue(comp_nh4.atom_specs[1].charge == 0)
 
+    def test_default_lib_version(self):
+        compound_lib = conop.GetDefaultLib()
+        if compound_lib is None:
+            warnings.warn("Compound library not available. Some functionality may not work as expected.")
+        else:
+            lib_version = compound_lib.GetOSTVersionUsed()
+            if lib_version < ost.__version__:
+                warnings.warn("Using old version of the compound library: %s" % lib_version)
+
 
 if __name__ == "__main__":
     from ost import testutils