Box positioning - cross-browser compatibility issue

Box positioning - cross-browser compatibility issue

I have a problem with a page layout on the website I am working on.
Here's a link
The blue box on the right hand side is looking good in IE and Firefox, but
it's too short (the text is too close to the bottom of the box) in Chrome,
Safari and Opera.
Here's the code for the box:
#testimon {
background: url("../img/ttm_bg.png") repeat-x scroll 0 0 transparent;
border-radius: 15px 15px 15px 15px;
border-top: 4px groove #00D1FA;
box-shadow: 0 1px 4px 1px #555555;
font-size: 14px;
height: 788px;
margin-top: 26px;
padding: 3px;
text-align: center;
width: 262px;
}
#testimon h4 {
color: rgba(255, 255, 255, 0.92);
font-size: 19px;
margin: 8px 0 17px 0;
text-shadow: 1px 2px 2px #1A1A1A;
}
#testimon p {
font-family:Georgia, "Times New Roman", Times, serif;
color: rgba(0, 0, 0, 0.88);
line-height:25px;
font-size: 14px;
font-style: oblique;
font-weight: bold;
text-shadow: 0 1px 1px #CCCCCC;
}
#testimon .quote {
font-size:25px;
padding:4px;
}
#testimon .signature {
color: #e6e6e6;
font-style: normal;
margin-bottom: 15px;
text-shadow: none;
}
#testimon .spacer2 {
background: url("../img/stars.png") no-repeat scroll 98px 0 transparent;
height: 13px;
margin: 31px 0 15px 0;
width: 262px;
}
Thanks for any help!