As of January 23rd, 2015, there has been an updated SAP CRM Service Manager v4.2 Installation Guide (document version 1.2) released on the Service Marketplace within the Installation and Upgrade Guides for SAP Mobile - SAP CRM Service Manager - SAP CRM Service Manager v4.2.
The revisions made are contained within the guide's "Service Manager Server Installation" section, specifically the section 3.1.1 - "Installing the SAP CRM Service Manager Application". Please note that there were inaccuracies in the previous document for the Linux installation steps.
Steps 1 - 8 have now been changed to reflect installation to either a Windows environment and most importantly to the Linux environment.
Please make a note of this and download the latest document at this time to ensure proper installation methods/steps are followed.