Wrong error when C1 requested, but anomer is C2.

The incorrect sequence DKDNpb1-OH throws an error, but it's incorrect/confusing and doesn't tell you that the C1 isn't available for this monosaccharide:
_There was a problem making the default sequence request: Problem with the metadata found in gmml for this linkage. The number of identified rotatable dihedrals: 2 is greater than the number of metadata items: 1 found for this linkage: Residue_linkage Index: 93877580155488, Name: DKDNpb1-1ROH, NumberOfShapes: 1, ids: 0Kn_A_2_?_?_?@C1 -- ROH_A_0_?_?_?@O1 O6, C2, C1, O1: -17.5039. C2, C1, O1, HO1: -55.1927._
It should say:
Problem with residue For these types of monosaccharides, the C2 is the reducing carbon.