DRM stands for Digital Rights Management. Digital Rights Management (DRM) is a way to protect digital media files, such as music, video, games from copyright infringement. There are several aspects to DRM; some pertain to online usage and some pertain to offline/local usage. But I will go straight to offline usage. Many aspects of DRM are run at the operating system level, and don't depend on that computer,machine,phone system being online. Digital Rights Management helps the operating system to protect the media files in many ways, for example in the S40v3 phone when you download a content such as J2ME Applications or Games from WAP it will get encrypted using a key that is only present on that specific s40v3 phone.There are many other method implemented to protect these J2ME's some of them are disabling the 'send via (insert method here) option' AND hiding these J2ME Applications from J2ME File Managers such as MobyExplorer,FileExplorer(j2me),MiniCommander or anything. But both these method still applies on unencrypted J2ME applications..
But for the encrypted J2ME Application or game, Even if you managed to transfer these encrypted J2ME to other phone maybe using your PC or Obex j2me application such as BlueFTP you just cant use that application or game on any other phone because it is already encrypted with the original phone special key. Identifying DRM protected is very easy one of the easiest way is through opening it with a Zip file archiver since an unencrypted J2ME is just a zip file.. If the Zip file archiver throws an error about it does not know the format of the zip file or it assumed the zip file is damaged then there's a high probability that the J2ME is DRM protected one other way is to open it with a text editor or even better a hex editor, If you open it and it displays "application/java-archiveflcontent@fl.contentid.s40drmv1#" then it is protected but if it says "PK" then it is not cause PK is the magic character for a zip file..
There are many technical aspects of DRM that we could get into, but the important thing is to do some checking for yourself and develop your own opinion.