I will explain the problem with example :
1) I logged into server using telnet as user ompe:
2) From ompe i "su" into another account.

so if I do "who" i do not find any detail of the new account into
which I have finally logged in.

STEP 1 : after logging into ompe
ompe@PLAB1:enterprise/ompe> who | grep
ompe pts/12 Jul 16 12:37 (

after logging to new account using "su" from ompe
ent92@PLAB1:enterprise/ompe> who | grep
ompe pts/12 Jul 16 12:37 (

ent92@PLAB1:enterprise/ompe> who | grep ent92
-- No value returned

Can you tell me what i should do to trace these movements. even finger
does not give me the login status. (In finger also the ompe is
registered and ent92 is not)

Any help will be appreciated.