Parent has no Properties

[rhostager]

I am getting a lot of these errors. (Windows XP Professional, Firefox Browser):
message - this.parent has no properties

fileName - http://localhost:7633/zimbra/js/ZimbraC ... 0130033225

lineNumber - 3552

stack - ([object Object])@http://localhost:7633/zimbra/js/ZimbraC ... 33225:3552

([object Object])@http://localhost:7633/zimbra/js/ZimbraC ... 3225:14510

([object Object])@http://localhost:7633/zimbra/js/ZimbraC ... 3225:14437

([object Object])@http://localhost:7633/zimbra/js/ZimbraC ... 3225:14392

([object Object],[object Object])@http://localhost:7633/zimbra/js/ZimbraC ... 3225:14344

apply([object Object],[object Array])@:0

([object Object])@http://localhost:7633/zimbra/js/Boot_al ... 033225:541

([object Object],[object Object])@http://localhost:7633/zimbra/js/ZimbraL ... 033225:386

apply([object Object],[object Array])@:0

([object Object])@http://localhost:7633/zimbra/js/Boot_al ... 033225:541

([object Object],[object Object])@http://localhost:7633/zimbra/js/AjaxLog ... 33225:3746

()@http://localhost:7633/zimbra/js/AjaxLog ... 33225:3701

@:0
name - TypeError

[jholder]

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