Upgrading GWT from 1.7 to 2.4 using Maven - gwt

Question

In my project we are using GWT 1.7 and now we want to upgrade it to 2.4. We also using maven 1.6 to build project. I've changed all pom.xml files so they look like this:
<properties>
<gwt.version>2.4.0</gwt.version>
</properties>
<dependencies>
<dependency>
<groupId>com.google.gwt</groupId>
<artifactId>gwt-user</artifactId>
<version>${gwt.version}</version>
<scope>provided</scope>
</dependency>
<dependency>
<groupId>com.google.gwt</groupId>
<artifactId>gwt-servlet</artifactId>
<version>${gwt.version}</version>
<scope>runtime</scope>
</dependency>
</dependencies>
Now, when i'm trying to build project, it crushes with error:
[ERROR] BUILD ERROR
[INFO] ------------------------------------------------------------------------
[INFO] artifact not found - Unable to download the artifact from any repository
Try downloading the file manually from the project website.
Then, install it using the command:
mvn install:install-file -DgroupId=com.google.gwt -DartifactId=gwt-dev -Dversion=2.4.0 -Dclassifier=linux-libs -Dpackaging=zip -Dfile=/path/to/file
Alternatively, if you host your own repository you can deploy the file there:
mvn deploy:deploy-file -DgroupId=com.google.gwt -DartifactId=gwt-dev -Dversion=2.4.0 -Dclassifier=linux-libs -Dpackaging=zip -Dfile=/path/to/file -Durl=[url] -DrepositoryId=[id]
com.google.gwt:gwt-dev:zip:2.4.0
from the specified remote repositories:
central (http://repo1.maven.org/maven2),
smartgwt-maven (http://www.smartclient.com/maven2),
repo.pentaho.org (http://repository.pentaho.org/artifactory/pentaho),
java-net-maven2 (http://download.java.net/maven/2),
thirdparty.pentaho.org (http://repository.pentaho.org/artifactory/thirdparty),
Octo Technology Nexus (http://forge.octo.com/nexus/content/groups/public),
codehaus-maven-repo (http://repository.codehaus.org/org/codehaus/mojo/)
I've downloaded files gwt-2.4.0.zip and gwt-servlet-2.4.0.jar, and tried to mvn install both of them, and now i have in my .m2/repository/com/google/gwt/ 4 directories: gwt, gwt-dev, gwt-servlet and gwt-user, all of them have 2.4.0 category inside (some also have old 1.7.0) directory, but the build error still appears.
UPDATE
Now i've change version to <gwt.version>2.5.0-rc1</gwt.version> , started maven build, i saw when mvn was downloading the required package, but it appears again:
com.google.gwt:gwt-dev:jar:2.5.0-rc1
not found. I've downloaded the gwt-2.5.0.zip from google website, and there are a lot of .jar files inside, which one should i install?