<dependency>
    <groupId>postgresql</groupId>
    <artifactId>postgresql</artifactId>
    <version>9.1-901-1.jdbc4</version>
</dependency>

<plugin>
    <groupId>com.googlecode.flyway</groupId>
    <artifactId>flyway-maven-plugin</artifactId>
    <version>1.7</version>
    <configuration>
        <driver>org.postgresql.Driver</driver>
        <url>jdbc:postgresql://...</url>
        <user>...</user>
        <password>...</password>
    </configuration>
</plugin>

<dependency>
    <groupId>postgresql</groupId>
    <artifactId>postgresql</artifactId>
    <version>9.1-902.jdbc4</version>
</dependency>