ExRangeValidator fails when min is a string

[djay]

Traceback (innermost last):

Module ZPublisher.Publish, line 138, in publish
Module ZPublisher.mapply, line 77, in mapply
Module ZPublisher.Publish, line 48, in call_object
Module Products.CMFFormController.FSControllerPageTemplate, line 91, in __call__
Module Products.CMFFormController.BaseControllerPageTemplate, line 26, in _call
Module Products.CMFFormController.FormController, line 384, in validate
Module ZPublisher.mapply, line 77, in mapply
Module ZPublisher.Publish, line 48, in call_object
Module Products.CMFFormController.FSControllerValidator, line 58, in __call__
Module Products.CMFFormController.Script, line 145, in __call__
Module Products.CMFCore.FSPythonScript, line 127, in __call__
Module Shared.DC.Scripts.Bindings, line 322, in __call__
Module Shared.DC.Scripts.Bindings, line 359, in _bindAndExec
Module Products.PythonScripts.PythonScript, line 344, in _exec
Module script, line 41, in fgvalidate_base
<FSControllerValidator at /extranet/mnt/extranet/my-state/purchasing/information/ppce-made-to-measure/fgvalidate_base>
Line 41
Module Products.PloneFormGen.content.form, line 558, in fgvalidate
Module Products.Archetypes.Field, line 345, in validate
Module Products.Archetypes.Field, line 358, in validate_validators
Module Products.validation.chain, line 136, in __call__
Module Products.PloneFormGen.validators.ExRangeValidator, line 40, in __call__
ValueError: could not convert string to float: