When running addImplicitHydrogens(iAtomContainer) on an iAtomContainer of the sdf-file attached the error is
Exception in thread "main" org.openscience.cdk.exception.CDKException: IAtom is not typed! P
So this type of phoshpor is not recognized by CDK
CDK version used 1.3.7
There are multiple occurences of this atom type in the ZINC database.