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In the book "Peter Rabbit", originally written and illustrated by Beatrix Potter, Peter Rabbit is vaguely tan-colored, and definitely has a blue jacket. He gets into trouble. He does get caught in a thornbush (I think he loses his jacket?). Beatrix Potter always drew her characters in proportions very close to the actual proportions of the animals. Admittedly, no purple eggs. And no kids, Farmer Mac Gregor I believe is the only human character.
Is it possible that someone took the story Peter Rabbit and added some more "Easter" and "magic" elements to make more of a special? Maybe the two kids were reading the story, or something?
Or is it possible that you have confused two or more things together?
Could it have been this?
http://en.wikipedia.org/wiki/Here_Comes_Peter_Cottontail
Admittedly, I saw it many, many moons ago, but there was some weird stuff in it. It is certainly possible to mix up traditional Peter Rabbit stuff and specials like this, especially after many years.
Could it have been an adaptation of Br'er Rabbit? http://en.wikipedia.org/wiki/Brer_Rabbit
No, that wasn't it. I'm quite familiar with Br'er Rabbit, and it was most certainly an Easter Rabbit. There was a good versus evil plot, and the Rabbit was stuck in the thornbush/portal. The brother and sister had to save him, and purple eggs were absolutely involved. Cadbury eggs are purple. Were there ever any Cadbury Easter Specials?
- edit* It aired in the early 90's, in BC, Canada. Does that help?
I think I know what you're talking about. I can't find it anywhere but the only thing I can think of like that is "The Search for the Great Bunny" The girl was named Abigail and her grandmother gave her a magic chocolate egg that could grant wishes. She used that magic to find the Great Bunny, who had gone missing. Is that it?
Was it an adaptation of the children's book The Tale of the Great Bunny? I searched and found that - it does seem familiar. But what I saw was most certainly animated. The book was commissioned by Cadbury, which would explain why the eggs were purple. Anything alse on your end?
Edited by TanglemorphApparently the full title of the movie is The Tale of the Great Bunny: The Story of the Magical Underground World of Chocolate.
EDIT: The TV special seems to have been part of a 1997 Australian ad campaign: “The Land of Cadbury.” (per this page
)
Land of Cadbury video clip
(the TV special is mentioned in the comments)

I remember an Easter special with purple eggs and a tan Easter rabbit (wore a blue jacket) that got in trouble, there was something about a thorn bush. Any ideas?
Animation was closer to proper proportions, not super-deformed.