I have problems with aligning the list that uses images as bullets.
In Firefox everything works well, but in Opera and IE, the bullet images are moved up (see the screenshots).
How can it be corrected? What's wrong with them?

plus/minus list



HTML:
Code:
<h2>Advantages:</h2>
<ul class="pros">
   <li>number of the projects (over 100 posted daily!) and their variety.</li>
   <li>reasonable fees (5%, min. $5).</li>
   <li>interface and functions (invited only projects, featured, job listings).</li>
   <li>several withdrawal methods (cheque, Paypal, e-gold, wire transfer).</li>
   <li>quick withdrawals (up to a few days).</li>
   <li>own dedicated forum and support.</li>
</ul>

<h2>Disadvantages:</h2>
<ul class="cons">
   <li>no obligatory deposit.</li>
   <li>occasional problems with support.</li>
</ul>
CSS:
Code:
.pros { list-style-image: url('../images/icons/plus.png');}
.cons { list-style-image: url('../images/icons/minus.png');}
blue arrow list



HTML:
Code:
<ul class="arrow">
   <li><a href="#selectionofsites">Selection of the freelance market sites</a></li>
   <li><a href="#registration">Registering and passwords</a></li>
   <li><a href="#projects">Projects</a></li>
   <li><a href="#communication">Communication with a client</a></li>
   <li><a href="#language">Language</a></li>
   <li><a href="#reviews">Reviews</a></li>
   <li><a href="#competition">Competition</a></li>
   <li><a href="#mockup">Mockup</a></li>
   <li><a href="#deadlines">Deadlines</a></li>
   <li><a href="#prices">Prices and payments</a></li>
   <li><a href="#transfers">Money transfer and withdrawal</a></li>
   <li><a href="#rules">Admins and Rules</a></li>
   <li><a href="#dangers">Dangers</a></li>
</ul>
CSS:
Code:
ul.arrow
{
  list-style-image: url('../images/icons/arrow.png');
}

ul.arrow li a
{
  color: #0061A6;
  font-weight: bold;
  font-size: 14px;
  line-height: 18px;
  text-decoration: none;
}

ul.arrow li a:hover
{
  color: #1480cc
}

h2.arrow a
{
  padding: 0 0 0 15px;
  background: transparent url('../images/icons/arrow.png') no-repeat center left;
}
Thank you.