soapVar class not found

[hetal]

when i click on issue get error
INTERNAL APPLICATION ERROR

Class "SoapVar" not found

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[atrol]

I was not able to reproduce your problem using the given information.

Please provide detailed step-by-step instructions to reproduce the issue; the following additional information may also be useful:

- Exact version of MantisBT, PHP, Database, Web server, Browser and Operating System
- Relevant customizations (e.g. changes in config_inc.php, etc)
- Installed plugins or custom functions ?
- Was the MantisBT source code modified in any way ?