Images Not Displaying in Email

[mattmo]

I send a newsletter out via MailChimp, in which the template includes 2 jpegs. When I send it, and it comes thru on my iPad 2, the one jpeg is just a large black square, and the other is invisible. Both have hyperlinks attached, which work. The thing is, everything displays fine on my iPhone 4, which has identical email settings as my iPad. It displays fine on my wife's iPad 2, which also has identical email settings as my iPad 2. Several friends are also receiving the images fine on their iPads. The people at MailChimp ran a test, and could not find any reason for the anomaly.

Suggestions appreciated!