In eB web the document template gives default revision as 01 even if in rules it is not defined.
But when looked in the revision set rule it dosn't have the "01" label.
Revision rule is the method in which the document has the drop down option of the setted revision.While creating the document one can select the revision value that is pre-defined in the revision rule.
Revision rule can be set in the Director.In System Admin, Maintain List Values there is set Revision Rule Set.
But the above error accurs happened due to the default revision value of the document is set as 01 in that document template.
Go to the particular template an see it in default propeties and make the revision tab as blank.