Robots.txt file and 301 redirect issue

[brad21]

Here is an issue. The www version of the site is blocked through robots.txt file for the search engines. Now, if any actual user end up landing in the www versions then they are 301 redirected to the non-www version of the site.

Now the site has gained some good links but they are on the www version. So, here is my query, will the search engines be able to index those backlinks?