Based on this:
http://www-01.ibm.com/support/docview.wss?uid=swg21302789
I installed a 6.3.4.0 library manager to handle a handful of 5.5.3.0 library 
clients.  So far, the only issue we've had is our tape robot falling apart 
(unrelated).

-
Cameron Hanover
chanover AT umich DOT edu

"They that can give up essential liberty to obtain a little temporary safety 
deserve neither liberty nor safety." 
--Benjamin Franklin

On Oct 9, 2013, at 8:18 AM, Zoltan Forray <zforray AT VCU DOT EDU> wrote:

> We ran multiple 5.5 library clients to both 6.1 and  6.2 library managers
> for a few years with no issues.  All TSM servers are RH Linux.
> 
> As other folks have reminded me 'Not supported does not necessarily mean it
> doesn't work'
> 
> -------------
> Zoltan Forray
> TSM Software & Hardware Administrator
> Virginia Commonwealth University
> UCC/Office of Technology Services
> zforray AT vcu DOT edu - 804-828-4807
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> On Oct 9, 2013 8:04 AM, "Steven Harris" <steve AT stevenharris DOT info> 
> wrote:
> 
>> Hi all
>> 
>> I've painted myself into a corner.
>> 
>> I have a customer with TSM V5.5.6 and V6.2.4 instances hosted on AIX.
>> 
>> The original plan was to move the clients one at a time off V5 and onto v6.
>> The V5 database is too big to convert, and as the instance is over 10
>> years old I fully expect it to have database issues that may make a
>> conversion difficult.
>> 
>> The customer sees this as essentially wasted work and wants me to implement
>> TSM for VE as quickly as possible since most of those V5 clients are (now)
>> virtualized Windows and Linux boxes.
>> 
>> There are dual sites with TS3500s and TSS1120/1140 drives, with a library
>> manager on each.   I'd be mad to install anything other than TSM for VE at
>> 6.4, so I'll need the TSM for VE instance to be 6.3.4.  This forces the
>> library manager to also be 6.3.4, but library manager/library client is
>> only supported at n+1, so the V5 library client is not supported with the
>> 6.3.4 library manager.
>> 
>> It really would be a better option to go straight to TSM for VE if that can
>> be done.
>> 
>> Is anyone out there successfully running V5 lib client against V6.3 lib
>> manager?  Anyone got horror stories to tell?
>> 
>> Thanks
>> 
>> Steve
>> 
>> Steven Harris
>> TSM Admin
>> Canberra Australia
>>