To install m2eclipse, use the following Eclipse update site to install the core of the m2eclipse plugin. This Core update site contains a single component: "Maven Integration for Eclipse (Required)". When you install this component you will be installing all of the core Wizards, the POM Editor, Maven Repository integration, and Maven integration. This post provides a set of detailed instructions for installing m2eclipse 0.10.0.
m2eclipse Core Update Site: http://m2eclipse.sonatype.org/sites/m2e
IMPORTANT NOTE: You cannot upgrade from m2eclipse 0.9.8 or m2eclipse 0.9.9 to m2eclipse 0.10.0. If you are running m2eclipse 0.9.8 or 0.9.9 you must either uninstall m2eclipse from your Eclipse installation or start with a fresh installation of Eclipse.
To install this plugin in the Eclipse IDE:
Note about 0.9.8 Workspace Incompatibility: If you are using m2eclipse 0.10.0 with a workspace that contains projects created under m2eclipse 0.9.8, you must remove the workspaceState.ser file. The workspaceState.ser file is located within the workspace directory in $workspacedir/.metadata/.plugins/org.maven.ide.eclipse/workspaceState.ser. If you remove this file, m2eclipse 0.10.0 will regenerate it as needed.
m2eclipse Extras Update Site: http://m2eclipse.sonatype.org/sites/m2e-extras