DomainDeploymentOverlayTestCase fails on pure IPv6 if proxy is used

Description of problem:
DomainDeploymentOverlayTestCase fails on pure IPv6 machine with Unable to determine IP address from host name "2620:52:0:105f::ffff:8%eth0"

How reproducible:
Always on pure IPv6 machine if proxy is used

Steps to Reproduce:

1. export PROXY_PARAMS="-DproxySet=true -DproxyHost=proxy-01-ipv6.mw.lab.eng.bos.redhat.com -DproxyPort=3128 -Dhttp.proxyHost=proxy-01-ipv6.mw.lab.eng.bos.redhat.com -Dhttp.proxyPort=3128 -Dhttps.proxyHost=proxy-01-ipv6.mw.lab.eng.bos.redhat.com -Dhttps.proxyPort=3128"
2. ./integration-tests.sh -Dmaven.repo.local=$MAVEN_REPO_LOCAL -fae -Dmaven.test.failure.ignore=true -Dnode0=$MYTESTIPV6_1 -Dnode1=$MYTESTIPV6_2 -Dmcast=$MCAST_ADDRV6 -Dipv6 -Djboss.dist=$JBOSS_DIST -Dtest=DomainDeploymentOverlayTestCase -Dts.domain -DfailIfNoTests=false $PROXY_PARAMS

Actual results:
MYTESTIPV6_1=2620:52:0:105f::ffff:8

The following error was encountered while trying to retrieve the URL: http://2620:52:0:105f::ffff:8%eth0:8080/deployment0/SimpleServlet?

    Unable to determine IP address from host name "2620:52:0:105f::ffff:8%eth0"

The DNS server returned:

    Name Error: The domain name does not exist.

This means that the cache was not able to resolve the hostname presented in the URL. Check if the address is correct.

Your cache administrator is sysadmin-engops-jbossqe@redhat.com.

Expected results:
No error