I don't know if we're going to find the "transom" version. Here's the version from Songs for Swingin' Housemothers as Her Mother Never Told Her:

Her Mother Never Told Her
(Let Her Sleep Under the Bar)

On a cold winter evening the guests were all leaving,
O'Leary was closing the bar.
When he turned and he said to the lady in red:
"Get out you can't stay where you are!"
She wept a sad tear in her bucket of beer
As she thought of the cold night ahead;
When a gentleman dapper stepped out of the phone booth
And these are the words that he said:

"Her mother never told her
The things a young girl should know,
About those dashing young college boys,
And how they come and go (Mostly go).
Age has taken her Beauty
And sin has left its sad scar.
So remember your mothers and sisters, boys,
And let her sleep under the bar."

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