According to the [http://www.thaiopensource.com/relaxng/design.html#section:17 documentation of Relax NG], there is no way of telling a document the location of the Relax NG Schema as it is possible with a DTD. As our main editor at the moment is [http://www.oxygenxml.com oxygen], either a processing instruction has to be entered into the xml-file, or a validation scenario has to be entered into oxygen (via Dokument > Validieren > Konfiguriere Validierungsszenario). In order to keep things clean and not confuse the user with relative paths to a local copy, a link to the Relax NG schema on this server can be entered. However, as this server can be reached only via https, oxygen itself has to be configured to accept a secure connection. For this purpose, the SSL certificate of the it-dev server has to be downloaded (attached is a PEM-encoded version, see [http://www.gtopia.org/blog/2010/02/der-vs-crt-vs-cer-vs-pem-certificates/ this blog entry] on how to display and convert that file) and stored in the Java keystore. On Mac OS, this can be done via Keychain (Schlüsselbundverwaltung). Then, edit oxygen's Info.plist with the {{{Property List Editor}}} and add two lines under Java > Properties: * Key: {{{javax.net.ssl.trustStoreProvider}}}, Value: {{{Apple}}} (String) * Key: {{{javax.net.ssl.trustStoreType}}}, Value: {{{KeyChainStore}}} (String) You can also paste the following snippet directly into the {{{Info.plist}}} (in Java/Properties) {{{ javax.net.ssl.trustStoreProvider Apple javax.net.ssl.trustStoreType KeychainStore }}} Note that the {{{Info.plist}}} file is overwritten with every update of Oxygen. The link to the latest version of the schema root is {{{https://it-dev.mpiwg-berlin.mpg.de/svn/mpdl-project-content/trunk/schema/schema/echo/echo.rnc}}} Fingerprints of the key: SHA1: {{{FA 59 20 79 0E 28 80 18 CA 2D 00 F1 B2 18 EA B7 00 F1 51 BE}}} MD5: {{{10 FB 77 75 C4 3A 30 62 BE 20 77 D5 51 F2 E0 C8}}}