Jasig/uPortal — comment on commit 13eff32bdc408a6e14ad582ee6f181ff1ff62da1
File: uportal-war/src/main/java/org/jasig/portal/redirect/PortletRedirectionController.java line 98
By edalquist:

Take a look at org.jasig.portal.url.UrlStringBuilder for building the redirect URL. All of the param keys & values have to get encoded with the response encoding to be correct in all locales and that class does that. It may not currently fit exactly with the base external URL but it could likely be modified to support that approach fairly easily.