[Galaxy Ace S5830 Q&A, Help & Troubleshooting] Viper The Ripper:
It's the file call_card_person_info.xml which we need to mod

I extracted this info from I9000 forum, I hope it help us to mod the file I have a trouble opening this file with notepad ++ and using AXMLPrinter2.jar too

<?xml version="1.0" encoding="UTF-8"?>
<FrameLayout android:layout_width="fill_parent" android:layout_height="fill_parent"
xmlns:android="http://schemas.android.com/apk/res/android">
<LinearLayout android:gravity="center_horizontal" android:orientation="vertical" android:id="@id/callCardPersonInfo" android:layout_width="fill_parent" android:layout_height="wrap_content">
<RelativeLayout android:layout_width="wrap_content" android:layout_height="216.0dip">
<ImageView android:id="@id/photo" android:layout_width="216.0dip" android:layout_height="216.0dip" android:layout_centerHorizontal="true" />
</RelativeLayout>
<LinearLayout android:layout_gravity="center_horizontal" android:orientation="horizontal" android:layout_width="wrap_content" android:layout_height="34.0dip" android:layout_marginTop="0.0dip">
<ImageView android:layout_gravity="center_vertical" android:id="@id/birthIcon" android:visibility="gone" android:layout_width="wrap_content" android:layout_height="wrap_content" android:src="@drawable/call_birthday_icon" />
<TextView android:textSize="32.0sp" android:textColor="@color/twcolor001" android:gravity="center_vertical" android:id="@id/name" android:paddingLeft="4.0dip" android:paddingRight="4.0dip" android:layout_width="wrap_content" android:layout_height="36.0dip" android:singleLine="true" />
</LinearLayout>
<TextView android:textSize="18.0sp" android:textColor="@color/twcolor003" android:gravity="center_vertical" android:id="@id/phoneNumber" android:layout_width="wrap_content" android:layout_height="wrap_content" android:singleLine="true" />
<TextView android:textSize="18.0sp" android:textColor="@color/twcolor003" android:gravity="center_vertical" android:id="@id/city" android:layout_width="wrap_content" android:layout_height="26.0dip" android:singleLine="true" />
</LinearLayout>
</FrameLayout>

I've found this info too but It isn't from Gingerbread sources, I guess it's form Eclair :S

http://xdaforums.com/showthread.php?t=576310

Yeah...It's by default in Phone.apk

ORIGINAL FILE (call_card_person_info.xml) FROM GALAXY ACE

<?xml version="1.0" encoding="UTF-8"?>
<LinearLayout android:gravity="center_horizontal" android:orientation="vertical" android:id="@id/callCardPersonInfo" android:layout_width="fill_parent" android:layout_height="wrap_content"
xmlns:android="http://schemas.android.com/apk/res/android">
<RelativeLayout android:layout_width="fill_parent" [COLOR="blue"]android:layout_height="181.0dip"[/COLOR]>
<ImageView android:id="@id/photo" android:background="@drawable/incall_photo_border_lg" [COLOR="blue"]android:layout_width="172.0dip"[/COLOR] [COLOR="blue"]android:layout_height="166.0dip"[/COLOR] android:layout_alignParentTop="true" android:layout_centerHorizontal="true" android:contentDescription="@string/contactPhoto" />
<Button android:textAppearance="?android:textAppearanceMedium" android:textColor="?android:textColorPrimary" android:id="@id/manageConferencePhotoButton" android:background="@drawable/manage_conference_photo_button" android:layout_width="wrap_content" android:layout_height="wrap_content" android:layout_marginTop="16.0dip" android:text="@string/onscreenManageConferenceText" android:layout_alignParentTop="true" android:layout_centerHorizontal="true" />
<TextView android:textAppearance="?android:textAppearanceMedium" android:textSize="15.0sp" android:textStyle="bold" android:id="@id/elapsedTime" android:layout_width="wrap_content" android:layout_height="wrap_content" android:layout_marginBottom="3.0dip" android:singleLine="true" android:layout_alignParentBottom="true" android:layout_centerHorizontal="true" />
</RelativeLayout>
<TextView android:textAppearance="?android:textAppearanceLarge" android:textSize="28.0sp" android:gravity="center_horizontal" android:id="@id/name" android:paddingLeft="4.0dip" android:paddingRight="4.0dip" android:paddingBottom="4.0dip" android:layout_width="wrap_content" android:layout_height="wrap_content" android:layout_marginTop="-13.0dip" android:singleLine="true" />
<LinearLayout android:layout_gravity="center_horizontal" android:orientation="horizontal" android:layout_width="wrap_content" android:layout_height="wrap_content" android:layout_marginTop="-1.0dip">
<TextView android:textAppearance="?android:textAppearanceSmall" android:textSize="18.0sp" android:textColor="?android:textColorSecondary" android:id="@id/label" android:paddingRight="6.0dip" android:layout_width="wrap_content" android:layout_height="wrap_content" android:singleLine="true" />
<TextView android:textAppearance="?android:textAppearanceSmall" android:textSize="18.0sp" android:textColor="?android:textColorSecondary" android:id="@id/phoneNumber" android:layout_width="wrap_content" android:layout_height="wrap_content" android:singleLine="true" />
</LinearLayout>
<TextView android:textAppearance="?android:textAppearanceSmall" android:textSize="16.0sp" android:textColor="?android:textColorSecondary" android:ellipsize="end" android:id="@id/callTypeLabel" android:paddingLeft="10.0dip" android:paddingRight="10.0dip" android:layout_width="wrap_content" android:layout_height="wrap_content" android:maxLines="1" />
<TextView android:textAppearance="?android:textAppearanceSmall" android:textSize="16.0sp" android:textColor="?android:textColorSecondary" android:ellipsize="end" android:id="@id/socialStatus" android:paddingLeft="10.0dip" android:paddingRight="10.0dip" android:layout_width="wrap_content" android:layout_height="wrap_content" android:maxLines="2" />
</LinearLayout>

Working with Contacts.apk

ORIGINAL FILE (dimens.xml) GALAXY ACE

<?xml version="1.0" encoding="UTF-8"?>
<resources>
<dimen name="linked_contact_icon_size">20.0dip</dimen>
<dimen name="quickcontact_shadow_horiz">30.0dip</dimen>
<dimen name="quickcontact_shadow_vert">37.0dip</dimen>
<dimen name="quickcontact_shadow_touch">20.0dip</dimen>
<dimen name="[COLOR="Blue"]edit_photo_size">92.0dip</dimen>[/COLOR]
<dimen name="tab_height">40.0dip</dimen>
<dimen name="account_name_height">25.0dip</dimen>
<dimen name="contact_shortcut_frame_width">50.0dip</dimen>
<dimen name="contact_shortcut_frame_height">56.0dip</dimen>
<dimen name="list_item_padding_top">4.0dip</dimen>
<dimen name="list_item_padding_right">11.0dip</dimen>
<dimen name="list_item_padding_bottom">4.0dip</dimen>
<dimen name="list_item_padding_left">4.0dip</dimen>
<dimen name="list_item_gap_between_image_and_text">8.0dip</dimen>
<dimen name="list_item_gap_between_label_and_data">5.0dip</dimen>
<dimen name="list_item_call_button_padding">14.0dip</dimen>
<dimen name="list_item_vertical_divider_margin">5.0dip</dimen>
<dimen name="list_item_presence_icon_margin">5.0dip</dimen>
<dimen name="list_item_header_text_width">56.0dip</dimen>
<dimen name="group_title_width_normal">280.0dip</dimen>
<dimen name="group_title_width_delete">250.0dip</dimen>
</resources>

These are the file POROVOZ! meant, if we change it and compile the .apks again, it should work