You should contact RIPE (I think that is the ISP for that IP) about this:

Here is the info on whois.org on that IP

Search results for: 217.65.193.25


OrgName: RIPE Network Coordination Centre
OrgID: RIPE
Address: Singel 258
Address: 1016 AB
City: Amsterdam
StateProv:
PostalCode:
Country: NL

ReferralServer: whois://whois.ripe.net:43

NetRange: 217.0.0.0 - 217.255.255.255
CIDR: 217.0.0.0/8
NetName: 217-RIPE
NetHandle: NET-217-0-0-0-1
Parent:
NetType: Allocated to RIPE NCC
NameServer: NS-PRI.RIPE.NET
NameServer: NS3.NIC.FR
NameServer: SUNIC.SUNET.SE
NameServer: AUTH00.NS.UU.NET
NameServer: SEC1.APNIC.NET
NameServer: SEC3.APNIC.NET
NameServer: TINNIE.ARIN.NET
Comment: These addresses have been further assigned to users in
Comment: the RIPE NCC region. Contact information can be found in
Comment: the RIPE database at http://www.ripe.net/whois
RegDate: 2000-06-05
Updated: 2004-03-16


If you visit the RIPE database, you get further info that might be usefull:

% This is the RIPE Whois secondary server.
% The objects are in RPSL format.
%
% Rights restricted by copyright.
% See http://www.ripe.net/db/copyright.html

inetnum: 217.65.192.0 - 217.65.194.103
netname: MOBTEL-NET
descr: MOBTEL Mobilne telekomunikacije Srbija BK PTT
descr: Belgrade
country: YU
admin-c: KC146-RIPE
tech-c: RC441-RIPE
status: ASSIGNED PA
notify: radomir.curcija@mobtel.co.yu
mnt-by: RIPE-NCC-LOCKED-MNT
remarks: Maintainer RIPE-NCC-NONE-MNT removed and object
remarks: LOCKED by the RIPE NCC due to
remarks: deprecation of the NONE authentication scheme.
remarks: Please visit the following URL to unlock this object
remarks: http://www.ripe.net/db/none-deprecation-042004.html
changed: hostmaster@ripe.net 20001102
changed: ripe-dbm@ripe.net 20040504
source: RIPE

route: 217.65.193.0/24
descr: MOBTEL-NET
descr: MOBTEL Mobilne telekomunikacije Srbija BK - PTT
origin: AS15958
notify: radomir.curcija@mobtel.co.yu
mnt-by: MOBTEL-MNT
changed: radomir.curcija@mobtel.co.yu 20040328
source: RIPE

person: Kalman Cinkler
address: MOBTEL Mobilne telekomunikacije "Srbija" BK-PTT
address: Sektor Informacionih tehnologija
address: 11000 Beograd
address: Bulevar Nikole Tesle 42a
address: Yugoslavia
phone: +381 11 3013 444
fax-no: +381 11 3013 452
e-mail: kalman.cinkler@mobtel.co.yu
nic-hdl: KC146-RIPE
notify: radomir.curcija@mobtel.co.yu
changed: radomir.curcija@mobtel.co.yu 20000828
source: RIPE

person: Radomir Curcija
address: MOBTEL Mobilne telekomunikacije "Srbija" BK-PTT
address: Sektor Informacionih tehnologija
address: 11000 Beograd
address: Bulevar Nikole Tesle 42a
address: Yugoslavia
phone: +381 11 3013 455
fax-no: +381 11 3013 452
e-mail: radomir.curcija@mobtel.co.yu
nic-hdl: RC441-RIPE
notify: radomir.curcija@mobtel.co.yu
changed: radomir.curcija@mobtel.co.yu 20000828
source: RIPE


There you have a couple of names