File transfer from AS/400 to MVS

I hope someone out there can help us.  This should not be this difficult.
We are attempting to use FTP to send a physical file from our V4R1 AS/400 to
another company's system that is running MVS and OS/390.  to do this, we
execute the following two commands after entering the user id and password:
quote site recfm=fb lrecl=160 blksize=27840 primary=5 secondary=2 cy 
put ourlibrary/ourfile.member 'xxxx.xxxxxxxx.xxxx.xxx.xxxx.origbk(+1)'

This returns the following error messages:
550-SVC99 Return code=4 S99INFO=0 S99ERROR=38668 HEX=970C S99ERSN code
X'000042CE').                                                         
501 Invalid data set name "xxxx.xxxxxxxx.xxxx.xxx.xxxx.origbk(+1)".  Use MVS
Dsname conventions.                                                        

If we remove the "origbk(+1)", we get these error messages:
550-SVC99 Return code=4 S99INFO=0 S99ERROR=38668 HEX=970C S99ERSN code
X'000042CE').                                                             
550 Unable to create data set xxxxxxx.xxxx.xxxxxxxx.xxxx.xxx.xxxx for STOR 

We have tried EBCDIC, BINARY, and different NAMEFMT values to no avail.  Can
anyone tell me either what we're doing wrong or where a manual that explains
these error messages might be located?

Thanks.

Donald R. Fisher, III
Project Manager
The Roomstore Furniture Company
(804) 784-7600 extension 2124
DFisher@xxxxxxxxxxxxxxxxx