Depending on which shell is beeing used, change the setting of the prompt variable in the appropriate shells configuration file, one way would be to have it set as:
if ($?prompt) then
if ($term == "undefined" || $term == "linux" || $term == "screen" || $term == "ansi" || $term == "vt100") then
set term = "vt100"
set prompt = "%n@%m %~> "
else
set prompt = "%{\e]1;%m\a\e]2;%n@%m:%~\a%}%n@%m %~> "
endif
endif
In otherwords... In your psar3 account's .profile or .login file (there should be one or the other or both), there will be some code on a line that begins with the word "prompt"....
Go to your pgr1 account, and copy that line to the same file (.login, or .profile) for the pgr1 account. Then (simplest) logout/in to the account again and you should see the change.