vImage and Matlab

Hi,

I am writing a mex file under MacOs X and trying to use the vImage
library delivered with Xcode. I am using the vImageConvolve_PlanarF
function to speed-up the MATLAB convolution. The compilation ends fine,
but when I run the mex I got the message:

Unable to load mex file:
/Users/geppyp/Documents/work/Fingerprint/core/myconv2.mexmac.
dlcompat: dyld: /Applications/MATLAB7/bin/mac/MATLAB Undefined symbols:
_vImageConvolve_PlanarF


So, it seems that is not able to link to the right library.
Does anybody knows which path I should pass to the mex command and which
mex-switch I should use?

Thanks,

Geppy