BBC News - Labour suspends three ex-ministers over lobbying claims‏

"Stephen Byers, Patricia Hewitt and Geoff Hoon are under investigation over their apparent willingness to help a lobbying firm in return for cash.

They were secretly filmed by the Channel 4 programme Dispatches, but have denied any wrong-doing. "

I fear they might be true. Lobbying goes on at the highest levels of government, and is rarely frowned upon. Many of the Tory front bench have made fortunes from such a practice, and I doubt they're alone in this country.
In America, something like $4billion per year is spent on lobbying.

In the unlikely event they have done anything against the law it will be a technicality.

And rather than writing politicians off as corrupt, I would say it's part of a wider issue. Those salaries/whatever else they technically are don't pay themselves