This is what it says in Getting Started - Requirements:

Requirements
If you are using Oracle8i, utPLSQL takes advantage of a number of Oracle8i features, including autonomous transactions, invoker rights and native dynamic SQL. You can also, however, use utPLSQL on Oracle7 (7.3.4 and above) and Oracle8.
Requirements for using utPLSQL include:
ˇ The schema owning utPLSQL objects must have EXECUTE authority on the DBMS_PIPE package, as well as the ability to create tables and packages.
ˇ If you want utPLSQL to automatically recompile test packages for you, you will need to have UTL_FILE installed and configured to read from the directory or directories in which your package source files are located. 
ˇ Optional: ability to create public synonyms. The installation script will attempt to create public synonyms. If your schema does not have the authority to do so, these commands will fail, but utPLSQL will still be available for use in the owning schema.

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SF