Windows 8, Zotero 4.0.17.1, Zotero LibreOffice 3.5.8, Firefox Nightly 30.0a1 (2014-02-11)

1) Open Libreoffice
2) Insert citation
3) Insert bibliography
4) Insertion of bibliography fails, with message box
"Zotero experienced an error updating your document.

assignment to undeclared variable needUpdate"

firefox error console:
assignment to undeclared variable needUpdate integration.js:2292
assignment to undeclared variable needUpdate integration.js:2292
assignment to undeclared variable needUpdate integration.js:2292
assignment to undeclared variable needUpdate integration.js:2292
...

clicking the link brings me to chrome://zotero/content/xpcom/integration.js

zotero console output that seems relevant:
zotero(3)(+0000009): Zotero.Integration.Session.prototype.lookupItems@chrome://zotero/content/xpcom/
integration.js:2292
Zotero.Integration.Session.prototype.addCitation@chrome://zotero/content/xpcom/integration.js:2241
Zotero.Integration.Fields.prototype._processFields@chrome://zotero/content/xpcom/integration.js:1473

Zotero.Integration.Fields.prototype.updateSession/<@chrome://zotero/content/xpcom/integration.js:141
2
_fulfilled@resource://zotero/q.js:890
when/</<@resource://zotero/q.js:920
makePromise/promise.promiseDispatch@resource://zotero/q.js:574
defer/become/</<@resource://zotero/q.js:477
onTick@resource://zotero/q.js:166
setTimeout</setTimeout/<.notify@resource://zotero/q.js:81