[tasklist] Unable to connect to Bugzilla

Hi,
for my team is very important to get the task list by Bugzilla, but when 
I try to query I receive the following exception (after some seconds):

org.xml.sax.SAXParseException: Errore di conversione caratteri: 
"Malformed UTF-8 char -- is an XML encoding declaration missing?" (il 
numero riga potrebbe essere troppo basso).
    at org.apache.crimson.parser.InputEntity.fatal(InputEntity.java:1100)
    at org.apache.crimson.parser.InputEntity.fillbuf(InputEntity.java:1072)
    at 
org.apache.crimson.parser.InputEntity.isXmlDeclOrTextDeclPrefix(InputEntity.java:914)
    at org.apache.crimson.parser.Parser2.maybeXmlDecl(Parser2.java:1009)
    at org.apache.crimson.parser.Parser2.parseInternal(Parser2.java:486)
    at org.apache.crimson.parser.Parser2.parse(Parser2.java:305)
    at org.apache.crimson.parser.XMLReaderImpl.parse(XMLReaderImpl.java:442)
    at org.xml.sax.helpers.XMLReaderAdapter.parse(XMLReaderAdapter.java:223)
    at javax.xml.parsers.SAXParser.parse(SAXParser.java:314)
    at javax.xml.parsers.SAXParser.parse(SAXParser.java:89)
    at 
org.netbeans.modules.tasklist.bugs.bugzilla.Bugzilla.getBugs(Bugzilla.java:302)
    at 
org.netbeans.modules.tasklist.bugs.bugzilla.Bugzilla.getBugs(Bugzilla.java:169)
    at 
org.netbeans.modules.tasklist.bugs.bugzilla.Bugzilla.getBug(Bugzilla.java:130)
    at 
org.netbeans.modules.tasklist.bugs.bugzilla.BZBugEngine.doRefresh(BZBugEngine.java:145)
    at 
org.netbeans.modules.tasklist.bugs.bugzilla.BZBugEngine$1.run(BZBugEngine.java:88)
    at org.openide.util.Task.run(Task.java:136)
    at org.openide.util.RequestProcessor$Task.run(RequestProcessor.java:328)
[catch] at 
org.openide.util.RequestProcessor$Processor.run(RequestProcessor.java:670)

In the New Query I submit those parameters:
Bug Engine: Buzilla
Base URL: http://lambrusco/bugzilla (a working bugzilla server on my 
intranet)
Query String: 
short_desc_type=allwordssubstr&short_desc=&long_desc_type=allwordssubstr&long_desc=&bug_file_loc_type=allwordssubstr&bug_file_loc=&bug_status=NEW&bug_status=ASSIGNED&bug_status=REOPENED&emailassigned_to1=1&emailtype1=substring&email1=&emailassigned_to2=1&emailreporter2=1&emailcc2=1&emailtype2=substring&email2=&bugidtype=include&bug_id=&votes=&changedin=&chfieldfrom=&chfieldto=Now&chfieldvalue=&cmdtype=doit&namedcmd=All+Bugs&newqueryname=&order=Reuse+same+sort+as+last+time&field0-0-0=noop&type0-0-0=noop&value0-0-0=
(a working query that returns all open bugs)

You can help me?

Thanks

Francesco Bellentani