[Lazarus] CodeCompletion: Unit not found, compile ok

[Lukas Gradl]

I've a strange problem with Lazarus (1.3, SVN 45936M):

Im working on a Linux-X64-Workstation but the target of the current  
project is Win32/i386.

I have a TDBGrid (dbgFolderDocs) on my form.

I can compile the project, it runs correctly.

But while coding when I press the . in the line
for i:=0 to dbgFolderDocs.SelectedRows
an error occurs (it's german, i translated it, so it might be not the  
exact english error message):
Codetools, Error: 1
dbgrids.pas(37,65) Error: Unit not found: Variants

How can this be - the compiler can find the unit.

Any help appreciated,

Lukas