Thanks to bjoern and Peter, it's working now.
I've juste change the type string to text.

    <param name="regular_expression" type="text" size="50" label="Regular expression to find" />

regards, 
Siva

> Subject: Re: [galaxy-dev] unable to add tools in tool_conf.xml
> From: bjoern.gruening@pharmazie.uni-freiburg.de
> To: nsiva3@hotmail.com
> CC: galaxy-dev@lists.bx.psu.edu
> Date: Thu, 8 Mar 2012 17:13:50 +0100
>
> Hi Sivasangari ,
>
> your tools has an error. Tools with an error don't get listed. Can you
> show us the rec_expression.xml file?
> I guess you need to change the 'string' to 'text' or something like
> that.
>
> Cheers,
> Bjoern
>
> >
> > I've got a problem, i'm not able to add a tool in ttol_conf.xml.
> > Actually i can see one tool that i've added but when i put the second
> > Galaxy doesn't take it into account :
> >
> >
> > <section name="My_tools" id="mtools">
> > <tool file="mytools/tool_countGC.xml" /> <!--This is okay-->
> > <tool file="mytools/rec_expression.xml" /> <!-- It's not working !
> > -->
> > </section>
> >
> >
> > My paster.log gives that :
> >
> >
> > galaxy.tools ERROR 2012-03-08 16:07:57,849 error reading tool from
> > path: mytools/rec_expression.xml
> > Traceback (most recent call last):
> > File "/home/pmontalent/galaxy_dev/lib/galaxy/tools/__init__.py",
> > line 77, in load_tool
> > tool = self.load_tool( os.path.join( self.tool_root_dir, path ) )
> > File "/home/pmontalent/galaxy_dev/lib/galaxy/tools/__init__.py",
> > line 169, in load_tool
> > return ToolClass( config_file, root, self.app )
> > File "/home/pmontalent/galaxy_dev/lib/galaxy/tools/__init__.py",
> > line 340, in __init__
> > self.parse( root )
> > File "/home/pmontalent/galaxy_dev/lib/galaxy/tools/__init__.py",
> > line 446, in parse
> > self.parse_inputs( root )
> > File "/home/pmontalent/galaxy_dev/lib/galaxy/tools/__init__.py",
> > line 528, in parse_inputs
> > display, inputs = self.parse_input_page( page, enctypes )
> > File "/home/pmontalent/galaxy_dev/lib/galaxy/tools/__init__.py",
> > line 708, in parse_input_page
> > inputs = self.parse_input_elem( input_elem, enctypes )
> > File "/home/pmontalent/galaxy_dev/lib/galaxy/tools/__init__.py",
> > line 801, in parse_input_elem
> > param = self.parse_param_elem( elem, enctypes, context )
> > File "/home/pmontalent/galaxy_dev/lib/galaxy/tools/__init__.py",
> > line 813, in parse_param_elem
> > param = ToolParameter.build( self, input_elem )
> > File
> > "/home/pmontalent/galaxy_dev/lib/galaxy/tools/parameters/basic.py",
> > line 159, in build
> > raise ValueError( "Unknown tool parameter type '%s'" % param_type
> > )
> > ValueError: Unknown tool parameter type 'string'
> >
> >
> > Have you got aany idea ?
> > advance thanks,
> > ___________________________________________________________
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>
> --
> Björn Grüning
> Albert-Ludwigs-Universität Freiburg
> Institute of Pharmaceutical Sciences
> Pharmaceutical Bioinformatics
> Hermann-Herder-Strasse 9
> D-79104 Freiburg i. Br.
>
> Tel.: +49 761 203-4872
> Fax.: +49 761 203-97769
> E-Mail: bjoern.gruening@pharmazie.uni-freiburg.de
> Web: http://www.pharmaceutical-bioinformatics.org/
>