Customer check the information center, got the following definition for DBSERVERNAME:
DBSERVERNAME must begin with a letter and CAN INCLUDE ANY PRINTABLE CHARACTER, except the following characters:
A field delimiter (space or tab)
A newline character
A comment character
A hyphen, minus, or @ character
but customer got error message when they try to include "." in DBSERVERNAME parameter.
Check the source code, only the lower-case letter, numeric letter, underscore and dollar symbol can be accepted in DBSERVERNAME.