OGR and oracle (MS4W 1.5)

[listuser HH]

Hi all,

I started to test the new ms4w package - I like it. I tried the oracle 
connection with mapserver and ogr - both work fine.

The next thing I wanted to test was a ogr VRT with points from a x / y 
table. I get the message: ORA-12514: TNS:listener does not currently 
know of service requested in connect descriptor in <unnamed>. In the 
.ovf file I use the same connection like in the mapfile before 
(OCI:usr/pwd@//serverIp:port/dbName). I have to say that I don't use a 
TNS because the oracle instant client don't have a tnsnames.ora file and 
I wasn't sure where to put one. I hoped that this will not be necessary 
since the other connections work. Has anyone a hint?

Thanks and regards

Norbert