Hi,
We are having the same issue when using opendocument hyperlinks in Webi.
I have heard something about using logical names instead of server:port.Then there should be somewhere in the server a .properties file to convert the logical name to the corresponding server:port in each environment. But I have not been able to find information about this.
We have some links jumping from Webi report to ECC, so relative path is not possible, but I will try for Webi to Webi links.