Issues for Non-static method html

[Jusao]

I need a help :
How to correct the error :
themes/unicorn/views/main/layout.php [60]:

Non-static method html::escape() should not be called statically, assuming $this from incompatible context.
Thank
rolandkossou2004@gmail.com

[gsteja]

I need an urgent help

While running ushahidi web in local host using mamp on mac osx after installation either basic or advanced it shows error as given below

**An error was detected which prevented the loading of this page. If this problem persists, please contact the website administrator.

themes/default/views/header.php [92]:

Non-static method html::escape() should not be called statically, assuming $this from incompatible context**

Please provide me the solution to solve it.