R help - Nov 2007 - A question regarding two dimensional optimization with constraints

Hello,
	I have an optimization problem which I would like to solve in R but  
am not sure how to approach this.
	I have a cost function C which is quadratic in rx and ry (if it  
helps, the cost function is separable in rx and ry) and is always  
positive for all rx,ry.
	I wish to maximize C subject to two convex constraints both of which  
are quadratic in rx and ry (if it helps, both are separable in rx and  
ry) and always positive.

	I do realize that because the intersection of the two constraints is  
convex and the solutions lie on the boundary of the intersection and  
it is possible to arrive at the optima analytically.

	However I would like a numerical approach via some optimization  
libraries in R.
	Could someone suggest some pointers as to how i could go about   
solving this in R? Which libraries should I use?

	Thank you for your time and help.
	Regards
	Saptarshi