Gradle "ignores" custom Maven repository (FTP)

I have a very simple custom Maven repository set up on a remote server that I access using FTP. However Gradle seems to completely ignore the repository, although I’ve added it in the build script.

Here’s the repository definition:

repositories {
 mavenCentral()
    maven {
  credentials {
   username "<user>"
   password "<pw>"
  }
  url "ftp://<server>/repository"
 }
}

And here’s an example of trying to import one of the artifacts deployed on the repository:

compile group: "net.sf.beanlib", name: "beanlib", version: "5.0.5"

Importing artifacts available on Maven Central works fine. And if I copy the custom repository to a local folder and change the FTP to a file URL importing from there also suddenly works.

Am I missing something? I know using FTP and no real repository server is not the best solution, but as far as I can tell it should work, right?

As far as I know, Gradle only supports the ‘file’ and ‘http’ protocols for reading from Maven repositories. For publishing to Maven repositories, all Maven wagons are supported.