(19)

(11)

EP 1 374 637 A2

(12)

(88) Date of publication A3: 09.10.2003 (43) Date of publication: 02.01.2004 Bulletin 2004/01 (21) Application number: 01965411.0 (22) Date of filing: 10.09.2001

(51) International Patent Classification (IPC)7: H04S 5/00 (86) International application number: PCT/GB2001/004027 (87) International publication number: WO 2002/026000 (28.03.2002 Gazette 2002/12)

(84) Designated Contracting States: AT BE CH CY DE DK ES FI FR GB GR IE IT LI LU MC NL PT SE TR (30) Priority: 19.09.2000 GB 0022892 (71) Applicant: CENTRAL RESEARCH LABORATORIES LIMITED Hayes,Middlesex, UB3 1HH (GB)	(72) Inventor: SIBBALD, Alastair MaidenheadBerkshire SL6 1XL (GB) (74) Representative: Sharp, Alan Cooper  QED I.P. Services Limited,Dawley Road Hayes,Middlesex UB3 1HH Hayes,Middlesex UB3 1HH (GB)