firefox freezes system and was termianted automatically

[usergeorg]

Binary package hint: firefox-3.0

The system was blocked for user activity (100% system load) and after some minutes firefox was terminated automatically. Than system worked again and firefox could be started again.

User action befor crashing: opening another TAB and loading a page from internet (sub-page from samsung).

Expected behavior: firefox loades the page or shows an error massage why not possible to show the page (error,...)

Fehler: [Exception... "Component returned failure code: 0x80004005 (NS_ERROR_FAILURE) [nsIDOMLocation.host]" nsresult: "0x80004005 (NS_ERROR_FAILURE)" location: "JS frame :: file:///usr/lib/firefox-3.0.10/components/nsSessionStore.js :: sss_saveState :: line 1909" data: no]
Quelldatei: file:///usr/lib/firefox-3.0.10/components/nsSessionStore.js
Zeile: 1909
*************copy of code************
  /**
   * save state to disk
   * @param aUpdateAll
   * Bool update all windows
   */
  saveState: function sss_saveState(aUpdateAll) {
    // if crash recovery is disabled, only save session resuming information
    if (!this._resume_from_crash && this._loadState == STATE_RUNNING)
      return;

    this._dirty = aUpdateAll;
    var oState = this._getCurrentState();
    oState.session = { state: ((this._loadState == STATE_RUNNING) ? STATE_RUNNING_STR : STATE_STOPPED_STR) };
    this._writeFile(this._sessionFile, oState.toSource());
    this._lastSaveTime = Date.now();
  },
********************************************
The following line was highlited:
this._writeFile(this._sessionFile, oState.toSource());

Mozilla/5.0 (X11; U; Linux i686; de; rv:1.9.0.10) Gecko/2009042513 Ubuntu/8.04 (hardy) Firefox/3.0.10

(sorry for my mistakes in writing english)

Thanks.