drugbank: protein group problem

[micheldumontier]

When the target is a protein_group, then only identifier for the first member
of the group is returned. for instance a target id for olanzapine is
BE0004872, which is a protein group containing 3 members, P08588, P07550
and P13945, but applying :x-uniprot to BE0004872 returns only P08588.