[Xotcl] XOTcl1.5.6 and Tcl8.5b1

[Murr, Florian]

Dear XOTcl-guys!
I tried to upgrade from Tcl8.4+XOTcl1.5.3 (all my projects worked fine
here!) to Tcl8.5b1, but my projects won't run due to some XOTcl
problems.
The following snippet is extracted from my project and I tested it with
XOTcl1.5.5 (from WinTclTk) and XOTcl1.5.6 from ActiveState-Teacup.
But both failed with the same error message.
My guess: Non-positional Arguments don't work!

#
************************************************************************
*****
# The script:


Class X
X instproc ListOfStringsOption {{-default {}} {-cb {}} name} {
    if {$cb eq {}} { set cb "::set ::$name " } ;# global variable
    eval $cb \$default
}
::X create x1
::x1 ListOfStringsOption uu


#
************************************************************************
*****
# Error message:
can't read "default": no such variable
    while executing
"::set ::uu $default"
    ("eval" body line 1)
    invoked from within
"eval $cb \$default"
    (procedure "ListOfStringsOption" line 5)
    ::x1 ::X->ListOfStringsOption
    invoked from within
"::x1 ListOfStringsOption uu"