diff --git a/kalzium.spec b/kalzium.spec
index e5dd4e2..2cee936 100644
--- a/kalzium.spec
+++ b/kalzium.spec
@@ -1,5 +1,5 @@
 Name:          kalzium
-Version:       20.04.0
+Version:       20.04.1
 Release:       1mamba
 Summary:       Periodic table of elements
 Group:         Graphical Desktop/Applications/Educational
@@ -35,6 +35,7 @@ BuildRequires: libsonnet-devel
 BuildRequires: libstdc++6-devel
 BuildRequires: openbabel-devel
 ## AUTOBUILDREQ-END
+BuildRequires: libopenbabel2-devel
 BuildRequires: cmake
 BuildRequires: avogadro-devel
 Provides:      kalzium4 = %{?epoch:%epoch:}%{version}-%{release}
@@ -69,7 +70,9 @@ Requires:      libkalzium = %{?epoch:%epoch:}%{version}-%{release}
 %setup -q
 
 %build
-%cmake_kde5 -d build
+%cmake_kde5 -d build \
+   -DOPENBABEL2_LIBRARIES=%{_libdir}/libopenbabel-2.so
+
 %make
 
 %install
@@ -128,6 +131,9 @@ exit 0
 %{_kde5_libdir}/libscience.so
 
 %changelog
+* Sat May 16 2020 Silvan Calarco <silvan.calarco@mambasoft.it> 20.04.1-1mamba
+- update to 20.04.1
+
 * Thu Apr 30 2020 Silvan Calarco <silvan.calarco@mambasoft.it> 20.04.0-1mamba
 - update to 20.04.0