FT search works on 5.12, but NOT on 6.5.3

We have a strange problem with FT search on several databases.

The server park consists of 3 servers:

1 Linux /Domino 6.5.3CF1

1 Win2000/Domino 6.5.3

1 Win2000 /Domino 5.0.12

The following example describes the situation quite well:

We have a documentation database with replicas on every server in the domain. The data is syncronized with the same number of docs on each server.

If you search for the word “organisation”, the 5.0.12 server returns 77 hits.

The Linux/Domino 6.5.3 server returns 11 hits

The W2000/Domino 6.5.3 server returns 83 hits

The Linux/6.5.3 server also returns documents with no trace of the word “organisation” inside.

Another strange thing: On the 6.5.x servers, when you open one of the returned documents, the word “organisation” is never highlighted but the word before it may be.

On the 5.0.12 server the search word is highlighted correctly.

Please help