Internal error is thrown when searching ParameterType by valueType

[RKrahl]

This search should yield all numeric ParameterType, but raises InternalError:

>>> client.search("SELECT pt FROM ParameterType pt WHERE pt.valueType = 'NUMERIC'")
<suds.sax.document.Document object at 0x7f6ffe9cf7f0>
Traceback (most recent call last):
  File "<stdin>", line 1, in <module>
  File "/usr/lib/python3.6/site-packages/icat/client.py", line 557, in search
    raise translateError(e)
icat.exception.ICATInternalError: INTERNAL org.icatproject.core.IcatException

icat.log and server.log attached: apparently icat.server fails to cast the string in the search expression to enum.

icat.log
server.log