HttpProxyServlet and certificate validation

Hi,
I'm using smartgwtpower-4.1p-2014-07-22-nightly build and I have configured HttpProxyServlet to forward client's REST API request to a cross domain web services running on the same server (different port) which is self-signed.

I'm getting the following error:
javax.net.ssl.SSLHandshakeException: sun.security.validator.ValidatorException: PKIX path building failed: sun.security.provider.certpath.SunCertPathBuilderException: unable to find valid certification path to requested target
=== 2014-09-11 21:02:33,152 [l0-5] WARN HttpProxyServlet - HttpProxy - Fatal transport error: sun.security.validator.ValidatorException: PKIX path building failed: sun.security.provider.certpath.SunCertPathBuilderException: unable to find valid certification path to requested target

I'm wondering if there is a way to configure HttpProxyServlet to skip or turn off certificate validation?

Thanks!