Did you read document readme.doc.
It is content about upgrade:
Upgrade installations from previous versions
To install as an upgrade to an existing system, perform the following steps:

- Save a copy of your existing configuration files from the conf/ and
conf/nutch directories.

- If you have changed any plugin configuration files, save copies of these.

- Remove the following files and directories from the existing installation

o toss*.jar

- 1 -

o bin directory

o lib directory

o plugins directory

- Unpack the distribution the to existing installation

- Copy your saved configuration files back to the conf directory and make
changes as required. See below.

- Rebuild existing indexes. This is needed to support sorting of data in the
web service and is also useful to take advantage of the additional parser
related changes which have improved the text extraction and indexing process.
The search will still work with the old indexes, but sorting will not be
possible.

Here is an example procedure of upgrade installations.

Ralf Wieler (04.11.2008 20:04):
>Hi All,
>
>I got a bit stuck after doing update of a TWO system for Linux to version 7.3
>and tried to use the search for mail from webservice. in the past it worked
>nicely and as we did not implement the new search engine I thought searching
>would remain as it was before. But it is not!
>
>Has anybody an idea how to activate the "old" search again?
>
>Thanks for your replies.
>
>/Ralf
>
>
>Mit freundlichen Grüßen
>Ralf Wieler
>
>---------------- Your comments are very welcome ----------------
>
>RW Consult IT-Dienstleistungen Tel.: +49 2162 353580
>Dipl.-Ing. Ralf Wieler Fax.: +49 2162 353582
>Zweitorstrasse 23 mobile: +49 172 2520437
>41748 Viersen ralf.wieler@...
>Germany http://www.rwconsult.de
>------------------------------------------------------------------
>
>
>
>
>------------------------------------
>
>---------------------------------------------------------
>TWLinux is an INDEPENDENT users' mailing list.
>More details at: www.proteusworld.com/twusersgroup
>Admin: Sebastian Paul Avarvarei
>Yahoo! Groups Links
>
>
>
>
>!DSPAM:109,49108ddf116702362839998!
>
>

Best regards

Mykola Gudzenko
UCL Consulting
____________________________
tel/fax. (38044) 3905200 , ext - 211
ICQ: 286573322
email: Mykola.Gudzenko@...
http://teamware.ucl.kiev.ua
_____________________________