diff --git a/luametalatex-back-pdf.lua b/luametalatex-back-pdf.lua
index 39f1e48..a3ae559 100644
--- a/luametalatex-back-pdf.lua
+++ b/luametalatex-back-pdf.lua
@@ -68,13 +68,17 @@ local reset_deadcycles = {
 }
 token.luacmd("shipout", function()
   local pfile = get_pfile()
+  local total_voffset, total_hoffset = tex.voffset + pdfvariable.vorigin, tex.hoffset + pdfvariable.horigin
   local voff = node.new'kern'
-  voff.kern = tex.voffset + pdfvariable.vorigin
+  voff.kern = total_voffset
   voff.next = token.scan_list()
-  voff.next.shift = tex.hoffset + pdfvariable.horigin
+  voff.next.shift = total_hoffset
   local list = node.direct.tonode(node.direct.vpack(node.direct.todirect(voff)))
-  list.height = tex.pageheight
-  list.width = tex.pagewidth
+  local pageheight, pagewidth = tex.pageheight, tex.pagewidth
+  -- In the following, the total_[hv]offset represents a symmetric offset applied on the right/bottom.
+  -- The upper/left one is already included in the box dimensions
+  list.height = pageheight ~= 0 and pageheight or list.height + list.depth + total_voffset
+  list.width = pagewidth ~= 0 and pagewidth or list.width + total_hoffset
   local page, parent = pfile:newpage()
   cur_page = page
   local out, resources, annots = writer(pfile, list, fontdirs, usedglyphs, colorstacks)
diff --git a/luametalatex-baseregisters.lua b/luametalatex-baseregisters.lua
index 95c000f..7e4b7f7 100644
--- a/luametalatex-baseregisters.lua
+++ b/luametalatex-baseregisters.lua
@@ -117,9 +117,9 @@ end
 
 tex_variable(count_code, token.scan_int, 'suppressfontnotfounderror', 0)
 tex_variable(count_code, token.scan_int, 'outputmode', 1) -- The "traditional" default would be 0,
-                                                            -- but we do not actually support that.
-tex_variable(dimen_code, token.scan_dimen, 'pageheight', tex.sp'297mm')
-tex_variable(dimen_code, token.scan_dimen, 'pagewidth', tex.sp'210mm')
+                                                          -- but we do not actually support that.
+tex_variable(dimen_code, token.scan_dimen, 'pageheight', 0)
+tex_variable(dimen_code, token.scan_dimen, 'pagewidth', 0)
 
 tex_variable(count_code, token.scan_int, 'bodydirection', 0)
 tex_variable(count_code, token.scan_int, 'pagedirection', 0)