non-FIXT sessions: NPE accessing ApplVerID if previous Logon was not completely processed

In some cases the thread processing incoming FIX messages can get a NullPointerException accessing the ApplVerID
if the Logon process is not complete, e.g. because the counter party did not answer with a Logon response but continues
to send application messages.

In real ife, this issue was observed as a counter party sent many FIX messages without noticing a FIX re-login:

1. counter party sends many messages
2. QF/J sends logout
3. counter party continues to send many messages
4. QF/J forces disconnect due to Logout time-out (no 35=5 received so far)
5. process restarts
6. QF/J creates a new session
7. QF/J sends Logon
8. counter party continues to send many messages (but no Logon)
9. QF/J receives a NPE for every message from the counter party:

   [2012-11-08 14:44:26,644] [QFJ Timer] FIX.4.4:XXXAT->XXXFL:TEST-XXX-XXXFL-YYY: outgoing: 8=FIX.4.4|9=68|35=A|34=1079|49=XXXAT|52=20121108-13:44:26.640|56=XXXFL|98=0|108=30|10=124|
   [2012-11-08 14:44:26,699] [SocketConnectorIoProcessor-0.0] FIX.4.4:XXXAT->XXXFL:TEST-XXX-XXXFL-YYY: incoming: 8=FIX.4.4|9=375|35=8|34=65834|43=Y|49=XXXFL|50=BU/XXXFL|52=20121108-13:44:26.675|56=XXXAT|122=20121108-12:45:47|6=0|...
   [2012-11-08 14:44:26,712] [QFJ Timer] FIX.4.4:XXXAT->XXXFL:TEST-XXX-XXXFL-YYY: event   : Initiated logon request
   [2012-11-08 14:44:26,801] [QFJ Message Processor] FIX.4.4:XXXAT->XXXFL:TEST-XXX-XXXFL-YYY: event   : null
   java.lang.NullPointerException
           at quickfix.MessageUtils.toBeginString(MessageUtils.java:256)
           at quickfix.DefaultDataDictionaryProvider.getApplicationDataDictionary(DefaultDataDictionaryProvider.java:62)
           at quickfix.Session.next(Session.java:913)
           at quickfix.mina.SingleThreadedEventHandlingStrategy$SessionMessageEvent.processMessage(SingleThreadedEventHandlingStrategy.java:114)
           at quickfix.mina.SingleThreadedEventHandlingStrategy.block(SingleThreadedEventHandlingStrategy.java:77)
           at quickfix.mina.SingleThreadedEventHandlingStrategy$1.run(SingleThreadedEventHandlingStrategy.java:94)
           at java.lang.Thread.run(Thread.java:722)
   [2012-11-08 14:44:26,802] [SocketConnectorIoProcessor-0.0] FIX.4.4:XXXAT->XXXFL:TEST-XXX-XXXFL-YYY: incoming: 8=FIX.4.4|9=353|35=8|34=65835|43=Y|49=XXXFL|50=BU/XXXFL|52=20121108-13:44:26.676|56=XXXAT|122=20121108-12:45:47|6=0|...
   [2012-11-08 14:44:26,811] [QFJ Message Processor] FIX.4.4:XXXAT->XXXFL:TEST-XXX-XXXFL-YYY: event   : null
   java.lang.NullPointerException
           at quickfix.MessageUtils.toBeginString(MessageUtils.java:256)
           at quickfix.DefaultDataDictionaryProvider.getApplicationDataDictionary(DefaultDataDictionaryProvider.java:62)
           at quickfix.Session.next(Session.java:913)
           at quickfix.mina.SingleThreadedEventHandlingStrategy$SessionMessageEvent.processMessage(SingleThreadedEventHandlingStrategy.java:114)
           at quickfix.mina.SingleThreadedEventHandlingStrategy.block(SingleThreadedEventHandlingStrategy.java:77)
           at quickfix.mina.SingleThreadedEventHandlingStrategy$1.run(SingleThreadedEventHandlingStrategy.java:94)
           at java.lang.Thread.run(Thread.java:722)