Incorrect size of soapui jar at smartbear maven repository

I am trying to install org.urbanbyte.soapui plugin via gradle. 

....
maven {
        url "http://smartbearsoftware.com/repository/maven2"
      }
maven {
        url "https://plugins.gradle.org/m2/"
      }

....

classpath ("gradle.plugin.org.urbanbyte:soapui-gradle-plugin:0.4.3"){
 exclude module: "jtidy"
 exclude module: 'cajo'
}

However I get this error message: 

> Could not resolve all dependencies for configuration ':classpath'.
   > Could not download soapui.jar (com.smartbear.soapui:soapui:5.1.0)
      > Could not get resource 'http://smartbearsoftware.com/repository/maven2/com/smartbear/soapui/soapui/5.1.0/soapui-5.1.0.jar'.
         > Premature end of Content-Length delimited message body (expected: 11583801; received: 9064045

I checked this address and downloaded jar and jar is in fact not as big as the site claims. (it is around 9MB not 11MB).

Is error on the repository side or do I have some error in the gradle?

If the error is on the repository side, can it be fixed?

Thank you.