Tax due on company stock purchase plan

Hi all,
I've had a look at the key posts and done a search regarding taxation of stock purchase plans, but haven't found a post similar to my situation.
The company I work for pay out a bonus every year. At the time of the bonus payout I can opt to invest some or all of it into company shares. Any money I decide to invest in this way does not get subjected to income tax or PRSI. The shares must be held for 3 years at which stage I can do with them as I like.
At the time of purchase the price of the shares is not discounted, I get them at the market value of the day.
If or when I decide to cash in the shares, apart from CGT, what other tax am I liable for? Would I be right in assuming that by taking part in the scheme I am merely deferring income tax and PRSI?

Example:
€1000 of bonus invested in shares
€0 paid in tax and PRSI
3 years later sold for €2000
CGT to be calculated on €1000

Do I also owe income tax and PRSI on €1000 I initially invested?

Thanks for any help.

your only liability is for Capital Gains.
Once you've left the money invested for the full 3 years, there is no prsi or income tax to pay

more info [broken link removed]

Thanks very much for the info, tit's exactly what I was looking for!