Share your experience!
I already made a thread about this issue: http://talk.sonymobile.com/thread/132402
But I am wondering if any of the Xperia L users has colored notifications? I have only encountered people with the white-ish light for every notifications. The colored LEDs are only used in the theme selector, walkman and album app, charging and calling.
So this thread is more for checking if this is really a problem or not, because I don't want to send my device for repair, lose it for a few weeks, and get it back in the same state because it wasn't really a problem.. (and maybe get charged for repair costs..).
Did you try changing your Theme in settings? I think the notification color depends on it. There are a few notification apps for Xperias in Google Play that might work, but, I haven't tried them yet. They worked really nice on my Xperia U though.