Locating a schema over a network

Is there a way to access a schema using an IP address and UNC path?

For instance, doing something like xsi:noNamespaceSchemaLocation="//10.1.2.3/schemas/schema.xsd"

In Java 1.4.2 this appears to work, but in 1.4.1_03 it does not, I instead have to map a drive to \\10.1.2.3\schemas and then specify the location with xsi:noNamespaceSchemaLocation="S:/schema.xsd"

Unfortunately, the server is not an http, ftp, telnet, or gopher server, and of course using file:/// doesn't work because the scema isn't on the local system.

Thanks!
Jabba