Java service or servelet for monitoring application servers

The aim is to re-design an existing application (Java servlet) which monitors application services. The application is to be implemented as Windows Service (or Linux Deamon); alternatively Java servlet on top of Tomcat can be used, but service/deamon is preferred. It shall consists of following modules: simple core, modules which provide check functionality, one reporting module which delivers results and configuration files which describe which checks to run and what parameters to use for checks. Example of check modules: check disk space in target path, check if service/deamon is running, check DB connectivity (MS SQL and Oracle), run utility and parse results, execute SQL query (MS SQL and Oracle), find files or directories older than specified time, simulate opening a web page (use form authentication, navigate to page, parse status). Checks and reporting must not block indefinitely when resources are unavailable (for instance DB check must use a reasonable timeout). I'm looking for experienced developer who can create an elegant architecture, easy to extend by new functionality. Development specification is available upon signing NDA. The developer will receive code of the current application; copying is OK, even encouraged. Code (design) updates are to be delivered on daily basis. Deliverables: elegant design of the application (there is a large degree of freedom), application developed according to documentation including installation procedure, source code. Conditions: NDA, customer gets full rights on resulting code. Long term cooperation on maintenance and implementation of additional functionality is foreseen upon successful delivery.