Intermittent connection fail with Oracle

hi All, I am facing strange problem of connecting to Oracle 8.1.5 running on remote NT Server thru PHP. My configuration is as follows PHP 4.0.2 on Redhat 6.2 with Apache 1.3.12 and Oracle 8.0.5 client installed Remote DB : Oracle 8.1.5 running on Win NT. Problem is that, sometimes PHP connects with oracle successfully but sometimes it says, TNS could not resolve the Service name. But if I reload this error page 2-3 times, it connects successfully. The 2nd one, Sometimes i face the problem of retrieving the Varchar from Oracle, and this one is also intermittent. For varchar problem, I just have to recompile Apache and PHP, and then it works, but if it occurs then, thats the only option I do. But for Oracle connection resolution, I just reload the page 2-3 times and it connects. Can anyone guess where the problem is, is it related to version compatibility or something else.... Any help will be really appreciated Ajay Intec LLC, Florida, USA