ARCHIVELOG back-up issue

Hi,

Recently, I have been bugged by a peculiar problem.

My system particulars:

OS: Solaris.

DB: Oracle

SAP: ECC 6.0 A+J

I have been taking archivelog backups regularly with no hassle. but previous day, when I took archive backup the BRARCHIVE throws a message that there is no files found for back-up.

I checked the ORAARCH and found 2 files registered for 25th Jan 2011, but they are not getting backed up.

I am taking an online backup of ARCHIVE LOG as I can't afford to downtime the Java part.

Please help.