has access level exception

on a blank wiki try :
http://localhost:8080/xwiki/bin/edit/XWiki/FlightClass?xpage=editclass

you will have :
Error number 4001 in 4: Error while parsing velocity page Wrapped Exception: Invocation of method 'hasAccessLevel' in class com.xpn.xwiki.api.XWiki threw exception class java.lang.StringIndexOutOfBoundsException : String index out of range: -1

the exception is throws in getweb line 163 on the Utils class because fullname == ""

a simple fix can be to test the value returned by fullname.lastIndexOf(".");

but is it normal the fullname == "" here?