Commissions due after resignation?

[jpillen]

I resigned from a sales postion with a company in San Diego, Ca. They began changing the sales contracts and the sale force was required to sign as a condition of employment. The first change was that Sales people would not be paid commissions on sales that had not been paid by the customer at time of resignation even if the materials and or services had been shipped and received by the customer. Was this legal?
I requested an advance of my sales commissions prior to my resignation and was not paid my last paycheck after I had given notice. Am I entitled to my last paycheck. I was a fully commissioned sales person with that company.