Hi Lars,

Yes, it should be. All the default email subjects and messages are in XML language files:

<?xml version="1.0" encoding="utf-8" standalone="yes"?>
<languages>
    <language name="English" id="en">
        <episerver>
            <cms>
                <contentapproval>
                    <notifications>
                        <email>
                            <awaitingapproval>Review requested by {0}</awaitingapproval>
                            <calltoaction>Go to Item</calltoaction>
                            <cancelapproval>Review request canceled by {0}</cancelapproval>
                            <deleted>{0} performed an action on an item that has been deleted.</deleted>
                            <forceapproved>The entire approval sequence has been approved by {0} and is Ready to Publish</forceapproved>
                            <heading see="/episerver/cms/notification/project/email/heading" />
                            <noaccess>
                                <message>{0} performed an action on an item that you do not have access rights to.</message>
                                <subject>An action on an item that can no longer be accessed.</subject>
                            </noaccess>
                            <projecttitle>Part of project '{0}'</projecttitle>
                            <readytopublish>Approved by {0} and Ready to Publish</readytopublish>
                            <rejectapprovalstep>Declined by {0}</rejectapprovalstep>
                            <removed>
                                <generic>{0} made an action on an item, which has been removed since then.</generic>
                                <specific>{0} made an action on '{1}', which has been removed since then.</specific>
                            </removed>
                            <stepapproved>Approved by {0}</stepapproved>
                            <stepcountoftotalsteps>Step {0} of {1}</stepcountoftotalsteps>
                            <subject>
                                <awaitingapproval>Review request from {0}</awaitingapproval>
                                <cancelapproval>Review request canceled by {0}</cancelapproval>
                                <forceapproved>Entire sequence Approved by {0} and Ready to Publish</forceapproved>
                                <readytopublish>Approved by {0} and Ready to Publish</readytopublish>
                                <rejectapprovalstep>Content Declined by {0}</rejectapprovalstep>
                                <stepapproved see="/episerver/cms/contentapproval/notifications/email/stepapproved" />
                                <stepcountoftotalsteps see="/episerver/cms/contentapproval/notifications/email/stepcountoftotalsteps" />
                                <summary>Summary of Content Reviews</summary>
                            </subject>
                        </email>
                        <user>
                            <awaitingapproval>Awaiting your review</awaitingapproval>
                            <cancelapproval see="/episerver/cms/contentapproval/notifications/email/cancelapproval" />
                            <deleted see="/episerver/cms/contentapproval/notifications/email/deleted" />
                            <forceapproved see="/episerver/cms/contentapproval/notifications/email/forceapproved" />
                            <noaccess>
                                <message see="/episerver/cms/contentapproval/notifications/email/noaccess/message" />
                            </noaccess>
                            <readytopublish see="/episerver/cms/contentapproval/notifications/email/readytopublish" />
                            <rejectapprovalstep see="/episerver/cms/contentapproval/notifications/email/rejectapprovalstep" />
                            <removed>
                                <generic see="/episerver/cms/contentapproval/notifications/email/removed/generic" />
                                <specific see="/episerver/cms/contentapproval/notifications/email/removed/specific" />
                            </removed>
                            <requestedby>Requested by {0}</requestedby>
                            <stepapproved see="/episerver/cms/contentapproval/notifications/email/stepapproved" />
                            <stepcountoftotalsteps see="/episerver/cms/contentapproval/notifications/email/stepcountoftotalsteps" />
                        </user>
                    </notifications>
                </contentapproval>
            </cms>
        </episerver>
    </language>
</languages>

You can replace them as necessary and remove those you want to remain the same as the default. You should place the resulting XML language file in Resources/LanguageFiles (or whatever directory you have configured).