ND-2500A under Linux

Hi guys!
I’ve a strange problem with my NEC ND-2500A under Fedora Core1 Linux (kernel 2.4.22-1.2197.nptl): I use dvd+rw for scheduled backup every night, but not work correctly… If I launch the procedure manually, everything work fine…

scsi2 : SCSI host adapter emulation for IDE ATAPI devices
Vendor: HL-DT-ST Model: CD-RW GCE-8483B Rev: B105
Type: CD-ROM ANSI SCSI revision: 02
Vendor: _NEC Model: DVD_RW ND-2500A Rev: 1.06
Type: CD-ROM ANSI SCSI revision: 02

I found this in my dmesg output:

Attached scsi CD-ROM sr0 at scsi2, channel 0, id 0, lun 0
Attached scsi CD-ROM sr1 at scsi2, channel 0, id 1, lun 0
sr0: scsi3-mmc drive: 40x/48x writer cd/rw xa/form2 cdda tray
Uniform CD-ROM driver Revision: 3.12
sr1: scsi3-mmc drive: 40x/40x writer cd/rw xa/form2 cdda tray
udf: registering filesystem
UDF-fs DEBUG lowlevel.c:57:udf_get_last_session: XA disk: no, vol_desc_start=0
UDF-fs DEBUG super.c:1421:udf_read_super: Multi-session=0
UDF-fs DEBUG super.c:410:udf_vrs: Starting at sector 16 (2048 byte sectors)
UDF-fs DEBUG super.c:437:udf_vrs: ISO9660 Primary Volume Descriptor found
UDF-fs DEBUG super.c:440:udf_vrs: ISO9660 Supplementary Volume Descriptor found
UDF-fs DEBUG super.c:446:udf_vrs: ISO9660 Volume Descriptor Set Terminator found
UDF-fs: No VRS found
ISO 9660 Extensions: Microsoft Joliet Level 3
ISO 9660 Extensions: RRIP_1991A
UDF-fs DEBUG lowlevel.c:57:udf_get_last_session: XA disk: no, vol_desc_start=0
UDF-fs DEBUG super.c:1421:udf_read_super: Multi-session=0
UDF-fs DEBUG super.c:410:udf_vrs: Starting at sector 16 (2048 byte sectors)
UDF-fs DEBUG super.c:437:udf_vrs: ISO9660 Primary Volume Descriptor found
UDF-fs DEBUG super.c:440:udf_vrs: ISO9660 Supplementary Volume Descriptor found
UDF-fs DEBUG super.c:446:udf_vrs: ISO9660 Volume Descriptor Set Terminator found
UDF-fs: No VRS found
ISO 9660 Extensions: Microsoft Joliet Level 3
ISO 9660 Extensions: RRIP_1991A

Someone can help me?!
Thank you very much!