Remember when Steven Joyce used to be the man who can?

The Minister for everything, the Government's Mr Fix-it.

Not so much anymore.

Either he took his eye off the ball on holiday pay or, to be less charitable, the Government has wilfully ignored the problem which may see millions out of pocket.

The Holiday Pay Act is a mess: complex and onerous when applied to those on casual contracts or shifts.

As a result employers have been incorrectly calculating holiday pay for 12 years.

News of this time bomb has only surfaced in the last month.

But as it turns out, it should be no surprise to anyone. Least of all Mr Joyce and the rest of the Government.

Ever since the legislation was passed, payroll experts have been warning about the problem.

NZ Post were embroiled in a court battle over holiday pay, beginning in 2007. The case went all the way to the Court of Appeal. Ultimately they lost in 2012, paying out $12m to 22,000 posties and mail processing staff.

This should have been a red flag.

It seems the Government did make a stab at reviewing the Holidays Act in 2010. But the problems were dumped in the too-hard basket and no substantial changes were made. (Labour argues that the few changes that were made have only made things worse).

Workplace Relations minister Michael Woodhouse has refused to take responsibility for that, choosing to blame a working group of businesses and unions that was established to come up with some solutions back in 2010.

In Mr Woodhouse’s words, "it's just that the working group advising the minister of the day couldn't reach a consensus about what an appropriate simplification framework would look like".

And so companies went on, underpaying their staff by anywhere between $70 and $1800.

The true scale of the problem began to surface again in 2014, when the Unite Union began challenging employers about their calculations and initially won back $17,000 for 60 workers.

But, according to the experts, the new super-ministry MBIE has been slow – or even reluctant – to help with payroll advice or specifications.

Finally, another group was formed to re-look at the problem in April – and the enormity of the bungle has become clear.

From MBIE to Novopay and Police, and possibly other Government departments, it has spread to the private sector.

Fonterra confirms it's got problems which it's working to fix.

McDonald's is now casting an eye over its payroll system to make sure it’s complying with the law.

So far, eight MBIE Labour Inspectorate investigations into un-named businesses have found 24,000 workers are known to have been short changed, but the estimates blow out to two million.

The injustice aside, the cost, stress and inconvenience to business will be huge.

Remarkably, the Government is still refusing to take responsibility – and won't even act to change or clarify the law in question. Joyce has even dismissed the "small amounts" of money involved, which rather arrogantly misses the point.

He won't change the law because he says people won't want to accept lower entitlements.

This is a straw-man argument.

The intent of the law was that holiday pay can be calculated in two ways (either based on your average wage over the previous year, or the rate you were on the week you take the break). You get to take home the rate which pays out most.

That needs to be made clearer, and easier for employers (or whoever they contract to do payroll) to comply.

But instead of fixing the problem, Joyce seems more intent on saving face: placing the blame on Labour for passing the messy law.