Reading VMS backup tapes

Now that I have read in a few archival tapes and unpacked the simple ones (ANSI-D) I am looking at extracting files from VMS BACKUP tapes. I found a program vmsbackup originally by John Carey at Monash University in AU. It actually seems to understand my tape container format, maybe because it is practically identical to some other formats. But, it is complaining that my tape has 80-byte header records, and it wants 256. My tapes start out with VOL1, HDR1 and HDR2 80-byte records, then a tape mark and then the backup save set follows. I get the message : Invalid header block size: expected 256 got 80 So, does anyone know whether there is a version of this program that will handle a backup tape with 80-byte header records, or is there another program for extracting files from a VMS backup tape or save set that will run on Linux?