Something similar happened in a place i worked, we were each owed a month's wages when they called in the liquidators.
From what i remember, once the contract is breached in any way - e.g. by not giving the minimum notice period, then it is rendered invalid and you are no longer entitled to other stipulations of the contract, e.g. months pay in lieu of notice.
If you have been left short by the liquidator, then as angie said, dept of enterprise and employment will cover outstanding pay up to capped limits. The liquidator should forward on any forms you need to complete, or you could make a call to them and see if there is anything outstanding.
It took about 18 months for us to be paid by the department, as there were no funds available to the liquidator to pay us anything.
The government would not pay you for holidays owing or the notice period.