Even though building worked ok, linking to the resulting library libxmlsec1-openssl.so caused various symbol lookup errors such as: /usr/local/lib/libxmlsec1-openssl.so: undefined reference to `X509_OBJECT_get0_X509' /usr/local/lib/libxmlsec1-openssl.so: undefined reference to `ASN1_STRING_get0_data' As the problem only appears at runtime I bumped the revision. Approved by: ssl blanket