Zimbra 5.0.16 Funambol 7.01 Zimbra Connector 5.02 Funambol Sync 7.2.3 Blackberry Tour

I have Zimbra, Funambol, ZimbraFunambol Connector, and Funambol sync all working ok except for a small problem:

If I create an appointment on my Blackberry and sync, the appointment shows up on the Zimbra calender just as expected.

If I create an appointment on my Blackberry and add an invite, the appointment does not show up on my Zimbra calender and I see the following error in my ds-server.log

Can anybody help?

PS I have a new issue with the SyncJE client too, I'm going to post that next.
Code:
Exception trace:
	at ru.korusconsulting.connector.funambol.PhoneDependedConverter.getCalendar(PhoneDependedConverter.java:134)
	at ru.korusconsulting.connector.funambol.CalendarSyncSource.getSyncItemKeysFromTwin(CalendarSyncSource.java:186)
	... 28 more
Caused by: com.funambol.common.pim.converter.ConverterException: java.lang.NumberFormatException: For input string: ""
	at ru.korusconsulting.connector.funambol.CalendarUtils.convertFrom(CalendarUtils.java:1195)
	at ru.korusconsulting.connector.funambol.PhoneDependedConverter.getCalendar(PhoneDependedConverter.java:128)
	... 29 more
Caused by: java.lang.NumberFormatException: For input string: ""
	at java.lang.NumberFormatException.forInputString(Unknown Source)
	at java.lang.Integer.parseInt(Unknown Source)
	at java.lang.Short.parseShort(Unknown Source)
	at java.lang.Short.parseShort(Unknown Source)
	at com.funambol.common.pim.sif.SIFCalendarParser.getAttendee(SIFCalendarParser.java:765)
	at com.funambol.common.pim.sif.SIFCalendarParser.parse(SIFCalendarParser.java:375)
	at ru.korusconsulting.connector.funambol.CalendarUtils.convertFrom(CalendarUtils.java:1193)