tr command behaving unexpectedly

Im trying to execute the below command on our server to list files and replace the newline in the file list with spaces, but the character 'n' is getting replaced with a space, is there any environment variable that needs to be set in UNIX?

sh -c 'ls -trx /data/inbound/drm/DRM_PRCC_Category_Flat*.txt /data/inbound/drm/DRM_PRCG_Group_Flat*.txt | tr "\n" " " '

gives the output

Output from command ====>
/data/i bou d/drm/DRM_PRCC_Category_Flat_20090617_113245.txt
/data/i bou d/drm/DRM_PRCG_Group_Flat_20090617_113319.txt

I expect the output to be
/data/inbound/drm/DRM_PRCC_Category_Flat_20090617_113245.txt /data/inbound/drm/DRM_PRCG_Group_Flat_20090617_113319.txt

Funnily the same command is working fine on 3 other servers.

Is there any environment variable that needs to be set or any of the LC_ env variables that hav eto be changed?

Regards
Ramesh

You can use sh -c

'ls - trx /data/inbound/drm/DRM_PRCC_Category_Flat*.txt /data/inbound/drm/DRM_PRCG_Group_Flat*.txt |tr -d '\n'
or
tr -s '\n' ' '
if you want space in between.