#2458 Backup fails with Unlock ioctl failed : Invalid argument

[Anonymous]

I am running Webmin 1.25 on a Sparc Ultra 10 with
Gentoo linux.

Whenever I try to run a filesystem backup, with either
dump or tar and seemingly regardless of any settings,
the backup fails as follows:

Performing backup of /etc to /backup/FrigateEtc ..

Unlock ioctl failed : Invalid argument

The filesystem being backed up is ext3, as is the
filesystem being backed up to.

The backup target is an NFS share, and my desktop, a
dual-processor Athlon-MP system also running Gentoo,
can backup to this directory using Webmin without any
problems. Same Webmin version.

[Nobody/Anonymous]

Logged In: NO

Additional info:

After attempting backup the following is appended to dmesg:
sys32_ioctl(perl:26802): Unknown cmd fd(5) cmd(40045431)
arg(01019be8)

From miniserv.log:
192.168.0.2 - root [20/Mar/2006:03:35:45 +0000] "GET
/fsdump/backup.cgi?id=265801142820057 HTTP/1.1" 200 9819

[Jamie Cameron]

Logged In: YES
user_id=129364

Does it help if you go to the Webmin Configuration module,
click on File Locking, and select the Never Lock Files option?

Alternately, you could try installing the IO::Pty Perl module.

Failing that I am out of ideas, as this message really seems
to be coming from the tar or dump commands..