You can contribute directly to your spouses RRSP; see CRA website or any other resource that comes up with a google. But ya, comes from your limit. You could give the cash to her but then you run the risk of it being attributed back to you. You can lend her the money have her pay interest to you which helps avoid the issue.
http://turbotax.intuit.ca/tax-resour...ousal-rrsp.jsp