Created Unassigned: [€] as regular expression crashes gplex [13731]

Adding the euro sign € to a character set literal (i.e., [€]) crashes gplex, with error:

Index was out of range. Must be non-negative and less than the size of the collection.
Parameter name: index

Unhandled Exception: System.ArgumentOutOfRangeException: Index was out of range.
Must be non-negative and less than the size of the collection.
Parameter name: index
at System.Collections.BitArray.Set(Int32 index, Boolean value)
at System.Collections.BitArray.set_Item(Int32 index, Boolean value)
at QUT.Gplex.Automaton.NFSA.NState.AddClsTrans(Leaf leaf, NState nxt)
at QUT.Gplex.Automaton.NFSA.NfsaInstance.MakePath(RegExTree tree, NState startState, NState endState)
at QUT.Gplex.Automaton.NFSA.Build(AAST ast)
at QUT.Gplex.Automaton.TaskState.Process(String fileArg)
at QUT.Gplex.Program.Main(String[] args)
C:\Mischa\vhdl_gppg\ConsoleApplication1\ConsoleApplication2_vhdl\vhdllexer.lex(1,1):error 3:Index was out of range. Must be non-negative and less than the size
of the collection.
Parameter name: index

(Oddly, adding the euro sign between quotes seems to work just fine, as a workaround.)
Just my 2 cts. Keep up the good works!