Can my company deny me severance if I go to work for the company to which the work was outsourced?

My current company's employee handbook states that employees who are laid off are eligible for severance pay. My current job is being outsourced so my position is being eliminated. I was told I was eligible for severance pay but then when I was offered and accepted a position with the company to which the work was outsourced I was told I'm not eligible for severance because my employment is being continued, but with another company. I will no longer be employed by my current company and my next employment should have no bearing on my current eligibility for severance. I've been told if I do not accept the job wiht the outsourced provider I will be eligible for severance. Is this legal?I work in Mississippi, the company I work for is in Denver, CO,