Tax clearance certificate when leaving?

[Art]

I have been living in Thailand for six years, leaving the country once a year for a short time.  I have never been asked for a Tax Clearance Certificate when I left.

About two years ago, I saw comments on an Internet message board that such a certificate used to be required.  However, I just noticed on my Arrival/Departure Card from last year the following statement:

"6. Alien entering Thailand and having income or alien staying over 90 days in Thailand without income must possess a Tax Clearance Certificate from the Revenue Department before leaving Thailand.  If not, will not be permitted to leave."

My questions:

(1) Has anyone been asked for a Tax Clearance Certificate when leaving Thailand?

(2) I get a receipt when I file my income tax return.  Is this what is referred to above as a "Tax Clearance Certificate"?

[george]

No need tax clearance! The infamous tax certificate