.htaccess - htaccess RewriteRule in Wordpress -

i want custom rewriterule in wordpress.

i got page http://example.org/blabla, , want redirect http://example.org/blabla/qwerty on same page "qwerty" in paramater.

actually got this:

options +followsymlinks <ifmodule mod_rewrite.c> rewriteengine on rewritebase / rewriterule ^index\.php$ - [l] rewritecond %{request_filename} !-f rewritecond %{request_filename} !-d rewriterule . /index.php [l] </ifmodule> 

and i'm trying add under rewritebase /

rewriterule ^blabla/(.*)$ /index.php?post=1024&myparam=$1 [nc,l] 

but doesn't work. can 1 me this? post = 1024 post id of page "blabla" in wordpress administration panel.

thanks.

i use api anubhava told me.