[plt-dev] drscheme fails on start up

This is all I get in response to $ drscheme foo.ss & The window is blank. Created around 9am this morning. 


> /Users/matthias/plt/collects/drscheme/private/tools.ss: drscheme broke the contract 
>   (->
>    (->
>     (is-a?/c interface:top-level-window<%>)
>     (is-a?/c interface:area-container<%>)
>     (is-a?/c class:switchable-button%))
>    symbol?
>    void?) on 
>   drscheme:module-language-tools:add-opt-out-toolbar-button
> ; expected <(is-a?/c interface:area-container<%>)>, given: #f
> 
>  === context ===
> /Users/matthias/plt/collects/scheme/contract/private/blame.ss:54:0: raise-blame-error
> /Users/matthias/plt/collects/scheme/contract/private/arrow.ss:1437:3
> /Users/matthias/plt/collects/scheme/private/map.ss:18:11: map
> /Users/matthias/plt/collects/drscheme/private/module-language-tools.ss:137:6: register-new-buttons method in ...le-language-tools.ss:72:4
> /Users/matthias/plt/collects/drscheme/private/module-language-tools.ss:186:6: after-set-next-settings method in ...le-language-tools.ss:72:4
> /Users/matthias/plt/collects/drscheme/private/unit.ss:567:10: after-load-file method in ...heme/private/unit.ss:465:8
> /Users/matthias/plt/collects/framework/private/text.ss:358:4: after-load-file method in ...work/private/text.ss:87:2
> /Users/matthias/plt/collects/framework/private/frame.ss:1019:2
> /Users/matthias/plt/collects/scheme/private/class-internal.ss:3595:0: continue-make-super
> /Users/matthias/plt/collects/scheme/private/class-internal.ss:3595:0: continue-make-super
> /Users/matthias/plt/collects/scheme/private/class-internal.ss:3595:0: continue-make-super
> /Users/matthias/plt/collects/framework/private/frame.ss:505:2
> /Users/matthias/plt/collects/scheme/private/class-internal.ss:3595:0: continue-make-super
> /Users/matthias/plt/collects/scheme/private/class-internal.ss:3595:0: continue-make-super
> /Users/matthias/plt/collects/framework/private/frame.ss:1578:2
> /Users/matthias/plt/collects/scheme/private/class-internal.ss:3595:0: continue-make-super
> ...