Error encountered; please report this error to a wizard.

VerbLoc:Verb	Programmer	This	Player	Line
#350:_render_delete	#789	#350	#7542	14
#302:tell_www_page	#789	#350	#7542	21
#80:serve_page	#789	#80	#7542	42
#81:do_GET	#55	#7542	#7542	12
#81:do_null_command	#55	#7542	#7542	9
#80:do_null_command	#789	#80	#7542	1

You can cut-and-paste the following:

#350:_render_delete (this == #350), line 14: Type mismatch
... called from #302:tell_www_page (this == #350), line 21
... called from #80:serve_page (this == #80), line 42
... called from #81:do_GET (this == #7542), line 12
... called from #81:do_null_command (this == #7542), line 9
... called from #80:do_null_command (this == #80), line 1
(end of traceback)